Detecting and editing mobs as they spawn

[Mecblader]

Hello I am making a mod where i need to be able to detect when a mob spawns and then edit it by giving it a semi-random health and a custom NBT Lvl. Basically I need to be able to edit every mob that spawn via spawners and mob eggs. Also If any one knows how I can edit the name plate of named mobs to display this custom Lvl of mine. All help is appreciated. Thank You in advance!

[GotoLink]

EntityJoinWorldEvent will fire for mob spawners, egg, natural spawning, etc.

 

The "name plate" is probably called customNameTag in the code.