Fissure vs. Hammer Shot vs. Smashing Ground

[Von Csent]

Realistically, Hammer Shot is probably the best. If you you can't activate it because you have the bigger monster, just attack.

 

Seeing as though someone will only use these if the opponent's monster is bigger (unless the nuisance is Spirit Reaper, etc.), Hammer Shot will be guaranteed to be able to kill the primary target.