Zaun champions create random chem-mods that only they can use. Champions can be modded once, and mods can only be removed by benching the champion.

Your first Zaun mod will always be an offensive mod (Robotic Arm, Virulent Bioware) or a hybrid mod (Adaptive Implant, Shimmer Injector). Your second mod will always be a hybrid mod or a defensive mod (Unstable Chemtank, Hextech Exoskeleton). You can’t get double hybrid mods. Your third mod will always be the remaining category.

Juggernaut champions take less damage as their Health decreases.

Challengers gain bonus Attack Speed. When their target dies, Challengers dash to a new target and increase their Attack Speed bonus by 50% for 2.5 seconds.