Use Goblin Demolisher on defense against ground swarms; his bombs clear small troops. When damaged, he starts running toward a building and deals serious damage if he reaches the tower. That makes him both a defensive card and a sneaky attacker.
Tips
Once damaged he switches to kamikaze mode; use that as a counterpush.
A troop in his path can stop him in kamikaze mode.
He can't hit air.
Strengths
Offers splash damage plus surprise tower pressure.
Turns into an attack on his own after defending.
Weaknesses
Can't hit air.
His kamikaze phase is easy to stop with cheap troops.