I control:
Vampire Lacerator
Magus of the Mirror
it is the beginning of my upkeep
life totals:
Me: one life
opponent: fifteen life
what would happen if I sacrifice the mirror magus and use its ability?
I control:
Vampire Lacerator
Magus of the Mirror
it is the beginning of my upkeep
life totals:
Me: one life
opponent: fifteen life
what would happen if I sacrifice the mirror magus and use its ability?
If you do it before the Lacerator's ability resolves, then you switch with your opponent, making you 15 and them 1. Then when the Lacerator's ability resolves, it sees your opponent is at less than 10 life, so you don't lose any.
Fluttershy is best pony.