Flying, deathtouch, lifelink
Whenever you gain life, Rodolf Duskbringer gains indestructible until end of turn.
At the beginning of your end step, you may pay {1}{W/B}. When you do, return target creature card with mana value X or less from your graveyard to the battlefield, where X is the amount of life you gained this turn.
X is the total amount of life you gained this turn, regardless of any life lost. For example, if you gained 3 life this turn and also lost 2 life this turn, X is 3, not 1.