Cerulean Drake

Flying
Protection from red (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything red.)
Sacrifice Cerulean Drake: Counter target spell that targets you.

Harbinger of Spring

Protection from non-Spirit creatures
Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Black Knight

First strike (This creature deals combat damage before creatures without first strike.)
Protection from white (This creature can't be blocked, targeted, dealt damage, or enchanted by anything white.)

Bog Elemental

Protection from white
At the beginning of your upkeep, sacrifice Bog Elemental unless you sacrifice a land.

Blightbeetle

Protection from green (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything green.)
Creatures your opponents control can't have +1/+1 counters put on them.

Great Sable Stag

This spell can't be countered.
Protection from blue and from black (This creature can't be blocked, targeted, dealt damage, or enchanted by anything blue or black.)

Rayami, First of the Fallen

If a nontoken creature would die, exile that card with a blood counter on it instead.
As long as an exiled creature card with a blood counter on it has flying, Rayami, First of the Fallen has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, and vigilance.