Heh, LifeTime wont work if you need something to explode, it just makes stuff vanish when the timer runs out. What you need is a little more complex: A breakwound emitter trick.

Although I dont see the point of him having an instant timer if he's an actor that you'd like to run around with and control it yourself. I'd suggest using a self killing weapon that would make the bob-omb explode only when needed, and keep the explosion small and terrain friendly.

We could make the bob-omb even disarmable with having the gun as bob-omb fuse that gibs into a few pesky particles leaving the bob-omb helpless and making his payload obsolete and creating a lousy explosion if shot at. So in other words, the bob-omb will need his gun to make him explode at full power.

What if you made two versions, one that could fly and the other that used the jetpack as a detonator. It's always nice to have variety.

Also, [on the topic of making the bob-omb change to red before exploding], wouldn't it be possible to first have the bob-omb gib into an animated sprite that shows it getting steadily redder, and after a set amount of time it explodes? But then again I'm not that experienced with modding and wouldn't know, but it's an idea.

Except that all it's doing is gibbing into a totally useless block of animated pixels that will probably instantly terrain themselves, and anyways won't be able to gib after a time limit.