Leyline Prowler

Deathtouch, lifelink
{T}: Add one mana of any color.

Vampire Nighthawk

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Greed

Blossoming Bogbeast

Whenever this creature attacks, you gain 2 life. Then creatures you control gain trample and get +X/+X until end of turn, where X is the amount of life you gained this turn.

Veinwitch Coven

Menace
Whenever you gain life, you may pay {B}. If you do, return target creature card from your graveyard to your hand.

Willowdusk, Essence Seer

{1}, {T}: Choose another target creature. Put a number of +1/+1 counters on it equal to the amount of life you gained this turn or the amount of life you lost this turn, whichever is greater. Activate only as a sorcery.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Mortality Spear

This spell costs {2} less to cast if you gained life this turn.
Destroy target nonland permanent.

Bloodtracker

Flying
{B}, Pay 2 life: Put a +1/+1 counter on this creature.
When this creature leaves the battlefield, draw a card for each +1/+1 counter on it.