Does Blowfly Infestation create a loop with Hapatra, Vizier of Poisons?
The card text is as follows
'Whenever a creature is put into a graveyard from play, if it had a -1/-1 counter on it, put a -1/-1 counter on target creature.'
When a token dies it goes to the graveyard and then disappears, so it looks like you keep generating a token and killing it. Or does the generation of the creature allow you to cast in between.