Pre 1:00 1 minute stay next to the left opening of your top jungle in order to scout for an invade. For the early game, use your Q Infected Bonesaw to either poke the enemy champion or last hit a minion safely. Since you're a scaling champion, against matchups where you hard outscale, it's okay to be behind in minions or tower platings, as long as you don't die. Dr. Mundo is very vulnerable to ganks, so remember to ward at 3:00 (around the time the enemy jungler finishes clearing if he paths to top) if you see the enemy jungler start bot side. Against champions like Darius and Mordekaiser, last hit with Q Infected Bonesaw and allow the wave to shove to you. Just getting EXP from minions is good enough. If against champions like Nasus or Kayle, look to bully them on last hits with your Q Infected Bonesaw or poke by last hitting a minion with E Blunt Force Trauma. Once you hit lvl 6 and get your R Maximum Dosage, it is possible to all-in the enemy top laner so long as they don't have a combative summoner spell like Exhaust, Ghost, or Ignite. Remember to use your Teleport wisely, it is best to use in lane, because Dr. Mundo doesn't have the best Teleport angle to teamfights since he lacks CC or any good gap closer. Even though you're tanky, remember not to walk into fights if they have multiple instances of CC, as you can get one-shot since Dr. Mundo's primary tankiness can only be shown if he is allowed to press R, or heal from Warmog's Armor/his passive Goes Where He Pleases.

In the middle of the game, remember to pop your W Heart Zapper on targets that can't escape for a while and while taking burst damage, as your W Heart Zapper will convert a portion of that damage back to fixed health when hitting an enemy champion. If you're fed and ahead, look to siege towers with either the help of your jungler and support shadowing you. You can easily 1v2 with enough of a gold advantage, but remember to buy a Control Ward when pushing ahead without your team. Never farm mid lane, because Dr. Mundo is significantly better when he is alone in the side lanes. For teamfights, try to think what kinds of crowd control they have. If you can reliably fight with your passive because they have low crowd control, look to contest objectives like Baron and Dragon. When against champions like Garen or Urgot, pop your ultimate while fighting with them at about 40% health to avoid being executed. When diving enemies under their turret, try to allow champions like Maokai or Alistar tank the turret for you, becuase you can easily get crowd controlled and die if the enemies focus you.

In the late game, remember to be the frontline for your team. Use Maximum Dosage when near 3 or more champions to boost your healing. Always remember to pick up your passive Goes Where He Pleases since the cooldown is zero. Ocean Drake and Mountain Drake scale the best with Dr. Mundo. You can easily match any split-pusher, so don't be afraid of going against an enemy top or mid laner 1v1. After full build, remember to buy an Elixir of Iron. Don't allow yourself to get crowd controlled, because even with your passive, you can still find yourself in a situation where you couldn't pop ultimate Maximum Dosage and die to tank killers like Vayne or Kai'Sa. As Dr. Mundo, try to target squishy backliners, because you don't have any damage against tanks or bruisers.

When it comes to objectives, remember that Voidgrub and Rift Herald have the same value as Dragon. Focus on CSing, since you don't need any kills to be ahead as Dr. Mundo. Don't try any Teleport roams, since it messes with your tempo and Dr. Mundo has no crowd control to help his team. Ideally, you want the wave to be either frozen or slow pushing towards your enemy top laner. Don't try itemizing resists based on your laner, rather buy items to be tanky against the whole enemy team and utility based on what you need. For example Sunfire Aegis for wave clearing and Warmog's Armor to outsustain your lane opponent.