Well, at first, I'll be straight-forward with you. While I might be completely wrong, it feels almost like you're trying to not answer the questions, if you feel that the answers could make me upset. In that case - as long as you give me any answer, like that you want to be the only one working on this project or that you need more time considering things like that. Of course I'm even more totally fine if you'll say that you could let me take part ;-). Every answer is more appreciated than none.
-1: Then I don't think that "bomb" fits the description, but rather sth. like "(power)shield"
Thinking of actual bombs I had an idea of a mechanic with bombs which one throws upwards, is detonated by the player at any point they wish but the explosion which covers about 50% of the field which has to be avoided.
4: for some reason I didn't see it recently...