Darksteel Citadel

Charge Across the Araba

Sweep — Return any number of Plains you control to their owner's hand. Creatures you control get +1/+1 until end of turn for each Plains returned this way.

Nikko-Onna

When Nikko-Onna enters the battlefield, destroy target enchantment.
Whenever you cast a Spirit or Arcane spell, you may return Nikko-Onna to its owner's hand.

Plains

Citywide Bust

Destroy all creatures with toughness 4 or greater.

Hundred-Talon Kami

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

Citanul Flute

{X}, {T}: Search your library for a creature card with mana value X or less, reveal it, put it into your hand, then shuffle.

Ugin's Conjurant

Ugin's Conjurant enters the battlefield with X +1/+1 counters on it.
If damage would be dealt to Ugin's Conjurant while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from Ugin's Conjurant.

Torii Watchward

Vigilance (Attacking doesn't cause this creature to tap.)
Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Marble Diamond

Marble Diamond enters the battlefield tapped.
{T}: Add {W}.

Moonlit Strider

Sacrifice Moonlit Strider: Target creature you control gains protection from the color of your choice until end of turn.
Soulshift 3 (When this creature dies, you may return target Spirit card with mana value 3 or less from your graveyard to your hand.)

Slaughter the Strong

Each player chooses any number of creatures they control with total power 4 or less, then sacrifices all other creatures they control.

Celestial Kirin

Flying
Whenever you cast a Spirit or Arcane spell, destroy all permanents with that spell's mana value.