Flying
{B}, Pay 2 life: Target creature gets -1/-1 until end of turn.
Whenever you lose life, draw that many cards. (Damage causes loss of life.)
A player loses life if they pay life.
If you pay life to cast a spell or activate an ability, you don’t draw cards until after you’ve finished casting that spell or activating that ability. You draw those cards before that spell or ability resolves, but after targets are chosen for it.