Castigate

Target opponent reveals their hand. You choose a nonland card from it and exile that card.

Plains

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {B}.

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Whenever you gain life, each opponent loses 1 life.

{1}, Sacrifice Scroll of Avacyn: Draw a card. If you control an Angel, you gain 5 life.

When Seraph Sanctuary enters, you gain 1 life.
Whenever an Angel you control enters, you gain 1 life.
{T}: Add {C}.

Enchant creature
As long as enchanted creature is white, it gets +1/+2.
As long as enchanted creature is black, it gets +2/+1.

Whenever another creature enters, you gain 1 life.

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Flying
When this creature enters, you gain 1 life and draw a card.

Whenever you gain life, put a +1/+1 counter on Celestial Unicorn.