indeed, love all of everything, but shouldn't the cost on locust swarm be 1 death and one life? instead of mentioning that in the ability.
And gravity bomb should probably have another name, as it sounds like a spell as is. perhaps magna-droid? no tha'ts terrible, i'm not very creative anyway though. and i'm assuming that it should target the highest hp? or lowest, if it were all the opposing creatures then it would just be like a 6 attack rain or fire that was endless (you could kill it but if would at least hit 6)