Nautilus mid is a very situational pick, but can be very strong and is often underestimated. I feel like his playstyle is similar to Fizz (except you're slow as a rock), in that once you hit your ult, their squishies melt. The thing with Nautilus though, is that he is relatively tanky, and his R isn't a skillshot.

If you don't believe me:

When to pick AP Nautilus mid:
- When they have a squishy mid laner
- Against Katarina (you stomp her hard)
- Basically whoever you feel like you can instagib

When NOT to pick Midilus:
- Against tanky mids like Cho'Gath
- Against Anivia
- Against Fizz

1) Depth Charge
2) Deathfire Grasp
3) Wait for the knock-up
4) Dredge Line
5) Titan's Wrath
6) Riptide
7) He should be dead by now, but Ignite him at 1HP to show him who's boss
8) THIS NEXT STEP IS CRUCIAL TO THE COMBO. CTRL+3 to Dance

Typical AP runes - I'm not going to get into too much detail. Magic penetration is a very important on Nautilus, so I usually go Greater Mark of Magic Penetration x9. After the armor runes nerf, a combination of Greater Seal of Health and Greater Seal of Armor runes is pretty standard. I take Greater Quintessence of Ability Power and Greater Glyph of Ability Power simply for the little boost of damage early.

Again, typical AP runes, except you get points in masteries such as Double-Edged Sword and Unyielding because you are melee.

Ignite

Do not take anything else but this. You need this for early kills.

Flash

Pretty much standard for almost all champions.

Starting Items


Crystalline Flask
Gives you sustain to survive through early levels.


Health Potion
I usually take two of these.


Mana Potion
You really only need one to start for that extra mana boost, given that you don't spam your skills needlessly.

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Core Items


Rod Of Ages
The shield from your Titan's Wrath scales off health. This item also makes you pretty tanky, and relieves you of your mana problems. Rush this, because like the name implies, it takes ages to stack it fully. I usually choose to build catalyst the protector first, because you don't need that much AP early.

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Deathfire Grasp
This is what allows you to instagib people. I usually build Fiendish Codex first (rather than Needlessly Large Rod) because CDR is nice; that and you don't really need much AP early. #1 most OP item for all mages.

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Items You Should Get


Liandary's Torment
The magic pen is great, and it synergizes with your E to deal double damage.


Rabadon's Deathcap
This item is pretty standard on AP carries. The only time I don't get this is when the enemy team is stacking MR, in which case it's better to build a Void Staff.


Void Staff
So yeah, as stated before, build this instead of Rabadon's Deathcap if the enemy team is stacking MR.


Zhonya's Hourglass
Do not forget that you are a melee champ that has to go into the middle of fights.[/columns]

This is your passive. It's useful for getting in a few more autos to proc more Titan's Wrath hits after catching your enemy. It's also very useful for lasthitting, as it deals bonus magic damage on-hit.

This actually does quite a bit of damage late game. Other than that, use it to pull yourself towards the enemy. The hitbox is quite wide (which can work to your advantage, or mess you up completely). After you hit 6, just ult the enemy and wait for them to get stunned before you use it to guarantee a hook.

This skills does A LOT of damage at rank 1. If you can manage to get two or three autos in, it chunks the enemy for half their health (as long as your shield doesn't get popped). The shield is really nice too, and scales with health. That being said, you are tanky enough so I don't really rely on the shield to soak damage. Instead, I wait for their damaging abilities to go on cooldown before I use it to ensure maximum damage. Even if you're low, the shield lasts for a ridiculous amount of time (10 seconds I believe), which can turn the fight around in your favour. Oh, and it's also a really nice auto-attack reset.

This provides a nice amount of CC, and is great for catching fleeing enemies (because it usually hits them 2-3 times if they are running away from you). At rank 5, you can position yourself in the middle of the wave to clear the entire minion wave with just one E. You can use this skill to farm if the enemy mid laner zones you hard - it has quite a bit of range.

After you get this, you can potentially instagib your enemy laner. It's not a skillshot, so once you target them with it, they're pretty much screwed.

At level 1, try to last hit. Your passive is really useful for that. If you are getting zoned really hard, wait for the wave to push to you and use Riptide to farm. PLAY SUPER PASSIVE AT LEVEL 1-2. You must survive until level 3 without taking too much damage.

At level 3, you will be able to chunk the enemy for at least half of their HP.

After you get some ranks in your Riptide, it will start to hurt a lot. Feel free to use that to harass.