Endless Sized Flyers

Flying Whenever a creature dealt damage by Baron Sengir this turn dies, put a +2/+2 counter on Baron Sengir. : Regenerate another target Vampire.

Each creature has "When this creature dies, choose target opponent. That player puts this card from its owner's graveyard onto the battlefield under their control at the beginning of the next end step."

Creatures don't untap during their controllers' untap steps. Whenever a creature enters, untap all creatures.

Flying Sacrifice a creature: This creature gets +2/+1 until end of turn.

Equipped creature has ": This creature deals 1 damage to any target." Equip (: Attach to target creature you control. Equip only as a sorcery.)

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.) Equip (: Attach to target creature you control. Equip only as a sorcery.)