The effect targets a monster card destroyed by battle.
Destroying a special summoned monster does not start a chain.
Destroys your Monster Cards
Special Summons from your Graveyard
Great with a phoenix deck, if your phoenix gets destroyed by battle, return it on to the field as a buffer for another attack or it is destroyed by card effect and comes back the next turn, pretty cheese..
With the warm worm card x3! (The card where opponent discards 3 random cards) maybe even pair it with a few cocoon of evolutions.
Imagine this x3 paired with time machines when its out x3 paired with shallow grave x3! Discard galore from opponents deck!
Your opponent has two monsters and you have just one, now he can't attack you directly. You have a monster in hand that requires a tribute and you want to play it next turn but your opponent kills one of your monsters. Etc. A very useful card if you ask me.