Volatile Zac

Event: Zac is in standby (does nothing or idle) Action: His entire body is filled with Lava, take Xerath's skin as a reference, he'd look as a lava container but still somewhat "flexible", only that also a few fire sparks are released from his body.

Event: Zac autoattacks Action: wherever zac autoattack hits, he leaves a burning orange sprite dot, some lava will spill the ground and by the time it touches the floor it gets reduced into ashes, into nothing.

Event: Zac is using an ability Condition: Any ability that hits the target. Action: Instead of the green slime, releases a lava cluster, it'll do a burning sound and some sparks will be released after touching the floor.

Event: Zac is cell-dividing Action: He'll make an explosion and 4 lava particles will fly away from him instead of green jelly.

Event: Zac uses Q Condition: hits target/s Action: His "fists" will make a mini-explosion.

Event: Zac uses W Action: Zac explodes himself, could look the same as when he cell-divides but in a minor size.

Event: Zac uses E Condition: Lands after self-launch. Action: Makes an explosion effect and reconstructs himself rapidly. Easy enough.

Event: Zac uses R Action: The animation would be some sort of bouncing lava. I'd take Brand's Pyroclasm as a reference for special effects.

Event: Zac dies Action: Many sparks fly upwards, and gets reduced into ashes on the ground.

Event: Zac recalls Action: Crouches and starts boiling himself, progressively reducing his figure into actual lava, and for the last seconds he launches himself, like erupting himself upwards.

So far, it's not like I'm all about the english language (because it's not my native language) so I'm doing my best to describe it so that I can help you imagine how Zac would look like in-game, with special effects an everything.

Correct, remove, replace, suggest, everything helps. Feedback is welcome, and so is your opinion. Everything can change as long as he's within the fire topic. :)