Abilities of Dr. Mundo
Spell skill priority is an important winning factor for Dr. Mundo. Understanding the abilities of Dr. Mundo in League of Legends is another. Below you can find all the relevant information on Dr. Mundo abilities. In order for item builds you should check the build for Dr. Mundo.
Passive: Goes Where He Pleases
Dr. Mundo resists the first Immobilizing effect that hits him, instead losing Health and dropping a chemical cannister nearby. Dr. Mundo can pick it up by walking over it, restoring Health and reducing this Ability's Cooldown.
Dr. Mundo also has significantly increased Health regeneration.
Infected Bonesaw
Dr. Mundo throws an infected bonesaw, dealing damage to the first enemy hit based on their current health and slowing them.
Dr. Mundo hurls his bonesaw, dealing currenthealthdamage*100% current Health magic damage to the first enemy hit and Slowing them by slowamount*100% for slowduration seconds.
If the bonesaw hits a champion or monster, Dr. Mundo restores healthrestoreonhitchampionmonster Health. If it hits a non-champion or non-monster, Dr. Mundo instead restores healthrestoreonhitminion Health.
Heart Zapper
Dr. Mundo electrocutes himself, dealing persistent damage to nearby enemies and storing a portion of damage he takes. At the end of the duration or on Recast, Dr. Mundo deals a burst of damage to nearby enemies. If the burst hit an enemy, he heals a percentage of the stored damage.
Dr. Mundo charges up a defibrilator, dealing damagepertick*4 magic damage each second for up to duration seconds to nearby enemies. Additionally he stores grayhealthstorageinitial of damage taken for the first grayhealthinitialduration seconds and grayhealthstorage*100% for the remaining duration as gray health and can Recast.
Recast: Detonate the defibrilator, dealing totaldamage magic damage to nearby enemies. If this hits at least one champion, Dr. Mundo restores grayhealthbigmod*100% of gray health, otherwise he instead restores grayhealthsmallmod*100% of gray health.
Blunt Force Trauma
Passive - Dr. Mundo gains bonus Attack Damage, increasing based on his max Health.Active - Dr. Mundo slams his “medical” bag into an enemy, dealing additional damage based on his missing Health. If the enemy dies they are swatted away, dealing damage to enemies they pass through.
Passive: Dr Mundo gains passivebonusad Attack Damage.
Active: Dr Mundo violently swings his "medical" bag, causing his next Attack to deal an additional additionaldamage physical damage, increased by up to maxdamageamptooltip based on his missing Health. If the enemy is killed, Mundo swats them away, dealing additionaldamage physical damage to enemies they pass through.
Maximum Dosage
Dr. Mundo pumps himself with chemicals, instantly healing a percent of his missing Health. He then gains Move Speed and regenerates a portion of his maximum Health over a long duration.
Dr. Mundo pumps himself with chemicals, gaining missinghealthheal*100% of his missing Health as max Health, speedboostamount*100% Move Speed, and regenerating maxhealthhot*100% max Health over duration seconds.
At Rank 3, both healing effects are increased by an additional bonuspernearbychampion*100% per nearby enemy champion.
FAQ on Dr. Mundo
What do you max first on Dr. Mundo?
Most Dr. Mundo pros max out 
Infected Bonesaw first.