LeBlanc Build Guide by Esoterica
[10.13] The Botlane Deceiver [Matchups / Strategy]By Esoterica | Updated on June 26, 2020
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Choose Champion Build:
Runes: The Assassin
+9 Adaptive (5.4 AD or 9 AP)
+9 Adaptive (5.4 AD or 9 AP)
Threats & Synergies
Ashe depends on poking out her lane until they are too low to contest her. Stay healthy behind minions or try to bait her Volley for your ADC and get aggressive when it is down. At 6, be certain you can react to her ulting you when you jump on her. It is not worth trying to bait out unless you or your team can capitalise.
Annies like to hold onto their pyromania stack for a chance to deal huge damage. You can easily poke from a safe distance and kite using chain, or wait out her rotation and jump her when she has no answer to you. If it is safe, W into her range to make her stun you, then blink back to avoid her ADC's follow-up. Baiting flash out early is key so that she cannot flash-R your ADC at 6.
Alistar cannot easily set up a kill on you and will be forced to use his charge to get you off his ADC. However, this means kills will be more complicated for you. Play aggressive and force his hand so he cannot save his abilities to flash-Q your ADC for an easy level 2 death.
Brand has effective AOE and huge threat with the stun. He can easily get you killed even when you play around his ranges. Bait out the pillar for your ADC. When you are hit by W or E, avoid the follow-up Sear by sidestepping. Do NOT jump him in a straight line, as he will Sear and you will simply blink backwards into its trajectory.
This matchup is heavily dependent on your ADC. You will never die to her if you are conscious of her traps, but you cannot poke her without her instant E-Q-Headshot trade, hurting you more than her. Employ the 'trading stance' and walk at her when she is about to CS. She will either get CS and take your QW, or AA you and lose gold. At 6, when you are brought low with Mirror Image, instantly path your clone to bodyblock for your or your ADC. You have 8 seconds.
It's not possible to trade with him using AAs or QW, as he will out-damage you or use Stand Aside to interrupt you. His AA range is shorter than your chain, making it possible to kite him out. Coordinate with your ADC to focus him as fast as possible in a trade or back off otherwise.
Ezreal relies heavily on abilities. When he tries to poke or burst a target down, you have an opportunity to punish him. When jumping him, delay using your chain as he will blink away on instinct. Do not risk missing it just to chain him before the blink. Play around minions and respect his damage at range. As he farms at a distance easily, try to intercept his shots when he last-hits cannon minions with Q.
Heimerdinger botlane is rare but always effective. He excels at pushing you in and ramping up to feel safe in his lane. Coordinate with your ADC to destroy his turrets as soon as possible, but without being baited into his damage as you walk up. Avoid the grenade and you have an easy kill if you land your chain.
Janna cannot kill you, but it will be difficult killing Janna. Her main weaknesses are that she relies on poke to create a HP differential, and that her shield can only protect one person. Bait the shield by going for one opponent and committing to the other.
Jhin excels at burst damage and punishing mistakes. Do not engage him when he is on his 4th bullet and try to punish his reload. Be aware that he will try to root you with Deadly Flourish and set up for an all-in, as he gains movement speed doing this. After trading with him, be prepared to sidestep the shot.
As the archetypal hypercarry, Jinx cannot do anything about you jumping on her for the whole of the laning phase. Dodge her only source of poke (Zap!) with a sidestep and avoid being rooted by Flame Chompers! and she will have nothing to answer you with. Just be aware of what her support is doing to retaliate. If she is fed lategame, your only hope is to wait for her to all-in someone else before blowing her up.
Jack of all trades in lane. Fight her in the wave so she cannot easily hit W and her Q damage is too spread out to matter. Her E's movement speed boost is negligible early so she is easy pickings. Post-6, chain her before she has the chance to ult, or wait after her dash to chain her. Do not let her decide the engagement first. She cannot ult unless you or a teammate has been hit with her AA or W, or have been CC'ed.
Karma easily punishes all-ins with high AOE damage, a shield and the risk of being rooted in the minion wave. Keep trades short and stay out of the minion wave so she cannot snag you with the Q explosion. The tether takes 2 seconds to root you.
Leona is more of a threat to your ADC than she is to you. Her weakness is a very inflexible engage, meaning if you kite her or avoid Zenith Blade (E) she cannot retaliate. Keep trades as short as possible with WQE instead of waiting for chain to snare, as she can jump on you easily and take off half your health with her passive.
Cosmic Binding hits two people, spelling doom for you when your Mirror Image activates. Spread out when you are low so they cannot stun you in invisibility. Bard has high damage but a telegraphed Q, meaning you can accept taking AAs if it means they lose their following meeps. Do not get stunned or it will hurt. You can easily avoid their ultimate with W, but the same cannot be said for your ADC. Be prepared to peel for them as you will be free to act.
Lucian excels at skirmishes and trading when he wants, discouraging you from gunning for him. However, he cannot dash when rooted. Additionally, Lucians want to dash forwards to finish their trading pattern, making them an easy chain target if your ADC is his target. Your clone can easily soak the damage from his ult when he tries to use it as a finisher.
The absolute bane of an assassin's existence. Kills will be impossible post-6, so your hope is to create a difference before then. her game plan is to polymorph you if you engage and poke with Glitterlance if you and your ADC are just farming. Play around her cooldowns and be aware of her positioning, as she easily chases single targets down. Respect her damage but try to focus the ADC.
Lux is a formidable matchup mid but not in botlane, as she must choose between trying to burst you or your ADC down. Her Light Binding is easy to avoid and should be punished if she randomly throws it out. Her shield is also not effective at early levels, and she may not always get her ADC with it as well. Focus the ADC but stay aware of where she is standing. Her QER combo at level 6 does ~60% of your HP.
Like midlane, Morgana cannot kill you, but you cannot kill Morgana. You cannot ensure chain will snare as she can Black Shield the target or try to bind you, forcing you to blink back. When her Q is down, she is extremely easy to exploit and she will have no damage to threaten you with. Poke her down post-6, as she easily turns engagements around with her ultimate if you or your ADC are bound. Black Shield has a CD of 26 seconds at rank 1.
MF's primary strength is poking using Double Up, and avoiding skillshots to stay healthy and avoid CC chains. Do not stay directly behind minions, or make sure one in front of you will take the bounce shot. Her Strut bonus resets upon taking damage, which you can easily do with Q if you distort into range. Be certain you can distort or flash out of her ultimate, as you will not survive a full barrage.
Nami relies on a telegraphed skillshot to peel for her or her ADC. You can easily decide engagements by trading normally and blinking back if she tries to punish you. When she moves forward to W you, move away from her so she cannot catch the healing bounce. Namis like to ult to start engagements and that simply doesn't work on you. Play the fight slowly and avoid her CC so she can only provide a little healing and slow.
Nautilus is known to be an oppressive catch/tank support, but LeBlanc negates some of his strengths as his hook is clearly telegraphed and he cannot protect his ADC from damage. W forward proactively to bait hooks or ults and simply return to safety. If he catches your ADC, burst down the enemy ADC with them to swing the trade in your favour. Do not play scared, as your ADC will take free damage or even die.
A catch support like Nautilus, Blitzcrank poses more problems as he has high burst damage and a silence on his ultimate to kill you for trying to deal damage. His hook is telegraphed but fast, allowing you to escape it. Play proactively and W often so that you're hooked with a Distortion return available, or you will have nowhere to go. If you are being chased, hold onto Distortion for as long as possible as he can hook you mid-dash or knock you up, leaving you stranded.
Pyke poses almost no threat to LeBlanc as his abilities are all telegraphed and easily responded to. Poke him or his ADC proactively and return to safety with W. He also cannot stop you from trying to snare with chain, as you have ample time to blink back. Post-6, be aware of how much damage you are taking and save Distortion or blink for his ultimate. Flash in a cardinal direction so that the arms of the 'X' do not catch you.
Rakan cannot do much to contest you poking his ADC or locking them down. However, he can easily jump onto your ADC and get out with Battle Dance with minimal fuss. With his low damage, focus the ADC first. Bait out his Grand Entrance for your ADC or prepare to retaliate when your ADC does get caught. Rakan is fragile and can be punished. Post-6, do not clump with your ADC and do not over-commit to damage. He can easily chain CC onto either of you and cause a death.
Senna's abilities are telegraphed and slow, giving you lots of space to play in. W proactively so that you can blink back if you're hit by the snare, and avoid standing behind minions so she doesn't get free damage by Q'ing minions. Her Curse of the Black Mist (E) is not an issue for you, as you can easily chain her while she moves in it.
Sett support relies on rushing at and overwhelming opponents. You can easily kite him with chain and avoid his damage. Avoid his true damage skillshot at all costs.
While Sona is extremely squishy and an easy target for ganks, she is known for huge damage in trades. Avoid letting her Q-AA you (especially with power chord available) and focus her, as she has very low HP and defences. Post-6, be prepared to blink back at any point in a kill attempt when she ults at you to save her ADC or turn the fight. Never let her open a fight with it.
While a dedicated healer, Soraka's true threat comes from her ability to stop your kill attempt at any time. When jumping in, DO NOT STAND THERE PRESSING W TO BLINK BACK. Play as if she will ALWAYS try to silence you when you engage. Her Q poke is frequent but easy to avoid, and she cannot hit both you and your ADC at the same time. Aim to punish her while walking out of her silence zone as fast as you can.
Swain snacks on immobile ADCS who have no answer for his range and threat. You can easily protect your ADC by engaging him first and baiting out his snare. He is fragile pre-6 and has little on-demand damage without his full combo. Swain has difficulty peeling for his ADC and relies on playing aggressively. Simply match his aggression and he will be forced to play safe and only poke.
Thresh has very little opportunity to stop you if you engage on his ADC. His hook is the slowest out of all the catch supports and can easily be baited, and his flay does little if you are only using W to get into range. The Box is far better at preventing escape attempts and you have everything you need to get out. If you are hooked, DO NOT W AWAY IMMEDIATELY as his flay will interrupt you. Be patient and trust you have the HP to survive the bit of damage from his ADC. If your ADC is hooked, focus the enemy ADC or Thresh if he's the only one in range. Your burst damage has the potential to turn the trade.
Twitch relies on ambushing you at early levels to get in free damage and permanently swing the lane. Make sure you coordinate with your ADC to punish him whenever he tries to do so, or you will take damage for nothing. If Twitch cannot be seen, assume he is hiding in a brush or coming from river to surprise you. Ambush invisibility lasts 10-14 seconds from rank 1-5.
Xayah can easily respond to your poke by attempting to snare you, forcing you to approach her at weird angles. She can also ult to avoid your damage. Space out your abilities when she has ult so you do not waste them hitting nothing. ALWAYS look at the angle of her feathers as being snared will hurt you immensely and ruin the chance of a kill.
Varus relies primarily on using Q to poke from an extreme range and R to foil a kill attempt. You will take a lot of damage trying to poke him as he can respond easily. Move erratically to avoid his Qs and try to work out if he is aiming for you or your ADC as he channels. Hail of Arrows only deals damage when it lands, but the slow can potentially lead to being engaged upon. If Varus ults your ADC, simply leave the tether AOE before re-engaging as it will no longer be able to spread to you.
Vayne is a more difficult ADC to kill, primarily because of her ability to Tumble (Q) and Condemn (E) to both dodge your chain and force you away to ruin your gank. Avoid standing near walls when engaging on her - unless you have a chain on her. Making her stun you into a wall instead of knocking you away keeps your chain in range for the snare to land. Post-6, play slowly and allow her to emerge from stealth before using double chains. Her damage suffers without tumbling and opens her to more CC from teammates.
Veigar out-damages you in the late-game, meaning early is your best chance at making his income suffer. DO NOT TRY TO W OUT OF HIS CAGE. When he casts cage, determine quickly if you're going to be caught on the edge or inside its range. W away if you'll be snagged. If you're trapped inside, sidestep within it as he cannot land his two other abilities. Veigar relies on his lane partner to CC you into the cage walls or deal damage to you while you're inside it. Bait out his cage and punish him when he cannot react.
Vel'koz excels at poking and dealing burst damage when landing his knockup. However, he is very vulnerable without his abilities, and cannot react if you jump on him and blink back when he tries to punish you. At range, he can only use his Q for damage and your ADC will mostly be safe. If your ADC is caught, Vel'koz is very fragile and can easily be killed.
A similar principle to Vel'koz, except his poke is more difficult to avoid as it's uncertain of he's trying to hit you or your ADC. However, he has nothing for you if you jump on him, as his stun's duration is at its minimum with no distance travelled. The strategy changes little post-6, except that you must be more aware of staying in lane with low life or with a tower dive imminent.
Zyra is one of the more threatening catch supports, as she has immense damage that becomes all-in potential at level 6. Try to bait out her snare before engaging and do not jump at her in a straight line, as her roots will simply hit you as you blink back. Be prepared to flash out of her ult as it can and will kill you from full health with the help of her ADC. Be aware that some Zyras like to stack seeds to do huge poke damage from one activation with her Q. Keep track of where she positions as she is least effective if she has to spawn plants on demand.
The bane of your existence. While she cannot punish like Soraka, it is nigh-impossible to kill her or her host as she pumps out healing and can easily give shields. Avoid this as much as possible as she scales much better than you.
With Caitlyn's extreme range and ability to follow-up chains with her Yordle Trap, the enemy botlane is forced to play defensively and cannot reliably engage you without invoking her ire in turn. However, Caitlyn relies on pushing to tower and sieging and LeBlanc cannot help her do this.
Ashe depends on securing the first hit to press the advantage with her slow, and relies on poke with Volley to whittle enemies down. You can easily play from brush to add to her poke and force enemies away from the wave, and her slow will help you land chains.
While Draven has extreme damage in lane and is easily a huge threat, his Stand Aside! can make you miss your chains and he cannot easily follow your lead.
Ezreal is purely a poke lane and relies on cheeky damage from around minion waves. With his help, you can poke enemies down into lethal range or secure the lane for him by pushing them away.
Jhin excels at skirmishes and burst damage, and can easily follow your snare with his own. He controls the space around him with traps and cannot be dived easily, allowing you to play offensively.
Theoretically, Kai'sa works best in short trades where she can cast an isolated Q and has clearance for W. If the minion wave permits, you can both do heavy damage from a single mistake on the enemy's part.
Jinx is very inflexible early and can only score kills in very irregular situations. With Zap! casting slowly and her traps having a short range, she cannot follow you at all unless you are punishing a failed engage where she can contribute damage. Go for counter-engages instead.
Lucian is strongest in laning phase and easily puts out huge, consistent damage with his trading patterns. Even without coordinating with your chain, he will easily win trades and can get kills with your assistance.
Miss Fortune is the queen of poke, but can't easily do her damage if the enemy botlane pressures her and steps around minions. You must threaten them and force them into her Double Up angles or she will not be able to assert dominance.
Sivir is notably self-sufficient and can foil ganks on her own, but she relies on poke to create a HP differential and operates on a different wavelength to you. She cannot engage alongside you and deals damage differently, making the lane awkward. Try to counter-engage instead.
Tristana is fragile and depends on measured aggression to get away with kills and jump back to safety. With your extreme damage and snare, you can combine with her slow and kill pressure to swing the lane in your favour.
Xayah is a fragile and high-damage ADC that relies on feather placement for a sweet root, but she cannot do that if she is forced to move into range. Try to play around her and counter-engage to surprise them with her root damage and your chain.
The poke ADC to rule all poke ADCs. Varus does not follow up easily but can dish out damage from a safe distance as the enemy ADC tries to farm. Poke with him until they are in kill range.
Vayne is supposedly a weak laner but has a good Level 2 and can secure kills with Silver Bolts... if you land the chain. Play aggressively, hope to lock the ADC down, and do not let the enemy engage first.
Runes: The Manipulator
+9 Adaptive (5.4 AD or 9 AP)
+9 Adaptive (5.4 AD or 9 AP)
+15-90 HP (lvls 1-18)
Support LeBlanc is a niche pick that aims to eliminate her two largest weaknesses: Poor waveclear, and a dependency on kills to get a lead and stay ahead.
As a support, she can create an advantage for her ADC and protect them while doing high damage on the side and potentially oneshotting wandering squishies. Her offense is extremely flexible and can adapt to the situation as necessary. She can also ward and clear wards safely without potentially dying to roaming enemies, and join ongoing 1v1s with her mobility to force a win. She doesn't need any protection, either!
LeBlanc is extremely fun and the quintessential high-skillcap champion, where you can always find improvement in how you play.
+ High, flexible damage
+ Safe warding and vision control
+ Extreme mobility to bait abilities and stay healthy
+ Strong jungle gank follow-up
+ Mirror Image clone bodyblocks for carries
As a support, LeBlanc retains her strengths while eliminating solo laner weaknesses. Her naturally high damage combined with Ignite can kill lane opponents as early as level 2, and she can extend a lead by roaming to assist the jungler in securing objectives or turn a lost lane around.
- No healing/shielding/utility
- Must choose between peel or extra damage
- Falls behind easily
- Slow power spikes
- Utility build de-fangs her
Dependent on a lead and items to shine, LeBlanc suffers when she cannot assist lanes or force kills where a standard support would serve much better. A lack of income can hurt her kill potential outside laning phase where she will be forced to prioritise chains and kite enemies instead of being a monster.
Supports have reduced gold income and less reliance on items to make space for vision control. Your teammates subconsciously avoid areas they cannot see into. Your jungler needs to keep track of the enemy jungler's movements to act accordingly.
Help set up objectives. Clear enemy wards and pink before ambushes. Your damage can swing skirmishes and snowball your jungler (who is as much of a lane as the other lanes are). Be certain you are watching the minimap to see if your jungler has been invaded and needs your help.
A majority of CC in the game is a linear skillshot. Using Distortion offensively straight at the enemy means they can aim for both you and your blink pad. If you form the habit of returning immediately, you are throwing away a blink and huge outplay potential.
|MIRROR IMAGE : When LeBlanc reaches 40% HP , she creates a controllable clone (with alt+M2) and becomes invisible for 1 second . The clone lasts for 8 seconds and automatically paths away from the source of the damage that created it. When Mirror Image triggers, ensure you control your clone to block damage for you or a carry, or path it toward safety while you stand still or hit a wall to fool pursuers.|
|SIGIL OF MALICE : LeBlanc fires a mark at her target that lasts for 4 seconds and can be detonated by damage from other spells. You mainly want to detonate it with Distortion or Ethereal Chains and will want to use Chains first when engaging so they have less time to react. The snare from Chains will detonate an existing mark.|
|ETHEREAL CHAINS : LeBlanc throws chains that latches onto the first target it hits. If it remains tethered for 1.5 seconds, it takes heavier damage and is snared for 1.5 seconds. It is necessary you hit Ethereal Chains to maximise your damage or Mimic it for 3 full seconds of CC on key targets. Staying in danger to wait for the snare can get you killed.|
|MIMIC : LeBlanc recasts her previously-used ability with new damage ratios. A copied Distortion at Rank 1 deals less damage than its basic counterpart, so use it for mobility or to get in range for Sigil of Malice- Distortion as a safe trading pattern. A copied Ethereal Chains neuters champions who need to move to deal damage, such as Akali and Lissandra.|
Early game, Electrocute can be activated with a Q-W-AA combo. When you have amassed items, you can kill at extreme ranges with W-R-Q-AA, using the first Distortion to close the distance and using flash when necessary.
A +6 AR shard handles some incoming ADC damage, but should be exchanged for +8 MR against strong mage supports. If you think laning phase will be no issue, take +15-90 HP as it scales best over the course of the game and amounts to more defences.
Losing Electrocute is an investment you must make good on, as your trades will add up to much less damage without it unless your ADC can follow your lead. Extra sustain from other runes in this route can make up for the missing threat!
Perfect Timing is only seen on the likes of Morgana, but allows for a single chance to save your life or make a risky engage that turns a duel around. Though it comes in at 14 minutes, takedowns hasten this cooldown, and this replica also contributes a fraction toward a Zhonya's Hourglass in the future. Enemies will gun hard for you and use ultimates, forgetting you have a replica at the ready!
A +6 AR shard handles some incoming ADC damage, but should be exchanged for +8 MR against strong mage supports. If you think laning phase will be no issue, take +15-90 HP as it scales best over the course of the game and amounts to more defences.
A short-range combo that requires the ADC is walking up to last-hit or a lane opponent facechecks early. This combo is fast and easy and usually doesn't allow for any retaliation. This is suited for being in the minion wave as they will not easily return fire with a hook or other CC to punish you.
Distorting into chain range allows you to play out of their threat range before going in, and is suitable for jumping on a farming ADC who must approach the wave. Chain must go first to minimise the chance they react to you and sidestep or move away. This combo can guarantee that you take return fire but will lock down your target for your ADC or jungler.
A safe and efficient trading combo that takes advantage of Mimic having poor ratios at Rank 1. Ideally, both Distortion casts deal their damage. This combo allows for two return blinks and is also hard to react to, as most enemies do not expect a Sigil inbetween jumps.
Ethereal Chains works identical to Charm where if you cast it and instantly Flash after, you can animation cancel it and make it more difficult to react to. The chain will originate from your new location. Flash over minions when they are prepared for you to use Distortion and surprise them.
By efficiently linking the snares of two Ethereal Chains casts, you can reach 3 seconds of CC on a key target. This is the highest damage achievable at Level 6 and should be your default when engaging. Use this on fed bruisers who must close the gap to heal or kill your carries, or mobile assassins like Zed, Akali or even Lissandra who rely on their movement abilities to deal damage.
Flash Distortion is the fastest assassination achievable with very little chance the enemy can react. LeBlanc's biggest issue in lategame is that enemies respect her power and stay close while maintaining their distance from her. This closes the gap as quickly as possible and covers 1,600 units. You must be relatively powerful to accomplish this, but can use Sigil of Malice and an AA to proc Electrocute.
Only use this combo if the target is facechecking your brush or already immobilised.
This does the most damage possible to a single target using every ability, but can easily go wrong if:
A) The chain is avoided, or;
B) they leave Sigil cast range or Flash out of your Distortion so your Mimic Sigil of Malice is wasted.
Kill or make them back to deprive them of XP and CS.
Secure first dragon with your jungler.
Take Distortion at Level 1 as it is your main trading tool and will help escaping any cheese strategies if they are waiting in brush or flashing over walls before minions spawn.
When entering lane, try to catch both the enemy ADC and the first trio of mage minions in the same Distortion and finish with an AA before blinking back. You want to help your ADC hit minions (without last-hitting them) to create a minion advantage and get Level 2 first. This forces the enemy to back off or risk huge damage when you hit Level 2 and potentially score a kill with the XP difference.
Take Ethereal Chains at Level 2 and your kill pressure spikes. A 1.5 second root on a fragile target is enough to force them to Flash away, and if they have nothing, they are dead. Make sure your ADC is in range to help you do this. Do not blame them if you are too far up and take more damage than you deal.
After this, do not touch the minion wave and let your ADC decide what to do with the lane. The only time you should be pushing with them is if the enemy ADC has died and you can push the wave to tower before their return. This will cause the enemy ADC to lose both XP and gold they cannot get elsewhere, creating an advantage for you.
Ideally, LeBlanc wants to play around the brushes and avoid being visible all the time. High damage supports rely on surprising the enemy with their range or aggression, and you cannot do much if you are stuck behind the minion wave. Playing separate from your ADC means they cannot engage on both of you at once and cause more trouble than it's worth... but also means they may find your ADC easy pickings. Do not neglect your carry just for some free damage.
If the enemy ADC or support prove slippery, consider relying on counter-engages to deal with them instead. As your ADC is engaged and Vayne tumbles forward or Ezreal blinks into range, you have everything you need to burst them and force them away. This will protect your ADC as the enemy will think twice about trying it again.
LeBlanc suffers the most under the enemy tower where she cannot easily deal damage and the enemy will hide behind minions. While Caitlyn has fantastic synergy, she depends on pushing to tower to completely lock the enemy out of playing the game. Be cautious of this and other ADCs who work the same.
If you see your jungler in trouble and the enemy botlane cannot follow, help them. Even without a help ping, you need to be aware of your jungler needing your help to win a 1v1 if they are invaded or are aggressed on in river.
Protect your siege champions to whittle down towers.
Set up ambushes or secure kills on lone enemies.
Make the enemy jungle unsafe for them.
When towers begin to go down and T2 boots enter the scene, the game tempo changes to be more open and laners will no longer stick to their minions. It is vital here that you focus on vision (laying down wards where enemies travel) and vision control (clearing enemy wards to make areas unsafe for them or protect your objectives). Facechecking is rare, but people do it when they think they're safe.
You want to switch to Oracle's Lens as soon as your quest evolves your Spellthief's Edge as LeBlanc thrives when enemies cannot see her movements. The additional warding power as a support links perfectly with her ability to assassinate.
At this point in the game, your prey is still the enemy ADC or support when you are alone. You should have the power you need to kill them from brush if they are unaware of you, and this can open up objectives for you to take. Other enemy laners can be safely engaged if you have assistance, as LeBlanc excels at locking stragglers down.
If you score a kill on the enemy jungler, consider how feasible it is to take dragon if it's available as the enemy cannot contest your jungler's Smite. Your presence at dragon also forces them back if they try to steal it or engage on your team.
Waves will continue to move around as champions revisit lanes to get more CS and keep ramping. Coordinate with someone to ambush them as LeBlanc can do this quickly and get back to the rest of her team. Punishing someone for trying to farm alone will force them to play more reserved and resort to taking jungle camps for income.
Lock down large threats and keep them at a distance from teammates.
Hunt down stragglers and push the advantage.
Support LeBlanc will undoubtedly have less power and agency than a midlane LeBlanc who has farmed and roamed with faster item spikes. However, this does not change that you can be a significant threat.
Before a fight breaks out (not during), assess several things:
1. Is there someone fragile enough I can kill near-instantly or without a chance they can escape?
2. Are there enemy assassins who can kill my carries?
3. Which abilities do the enemy team rely on to engage?
LeBlanc is and always be an assassin first. If you see an opportunity to kill an enemy and get to safety without dying, you are instantly giving your team a fighting chance as it becomes a 4v5 and your abilities will be back up in time for the actual teamfight.
If you do not see an enemy gathered with their team, it is a 99% chance they are hidden somewhere and preparing to dive you or your ADC/APC. If the fragile enemies you can kill are inaccessible to you, act as a bodyguard instead and punish or even kill enemies trying to dive your backline. You have two Ethereal Chains to make use of.
If there is nobody you can dive and nobody will dive you, the best case will be to work front-to-back, starting with their tanks and burning through them. Ethereal Chains is perfect for fighters like Darius or Irelia who depend entirely on sticking to targets to sustain themselves and kill. Tanks will quickly melt when they cannot move.
When the fight is won, determine if it's possible to pick up an extra kill or two as the survivors try to leave and base. Distortion and Ethereal Chains is a death sentence if teammates follow your lead, and you will widen your window of opportunity to hit towers or even inhibitors. Take this opportunity when the enemy is not there to ward. Being unable to move around in their own jungle severely cripples their ability to respond to fights or get to objectives without being engaged on.
Chapter code formats taken from: https://www.mobafire.com/league-of-legends/build/making-a-guide-101506
Introduction image: 朋友是只猫 on Weibo