There's a lot of objects in the game that have a variety of animations, beyond a single active and inactive one (like doors).
Some objects, like spell objects, have starting animations, sustains and then falloffs -- and I think it'd be nice if there was a way to trigger those in particular as well.
.gob anim would, if possible, be able to make an object like, say, various spell objects, remain invisible before being actually applied and then told to remain there.