Darksteel Citadel

Creatures can't attack you unless their controller pays 2 for each creature they control that's attacking you.

Flying When this creature enters, you may search your library for an artifact creature card, reveal it, put it into your hand, then shuffle.

Whenever one or more creatures attack, you may have target attacking creature gain double strike until end of turn.

At the beginning of your upkeep, each player may put two +1/+1 counters on a creature they control. If a player does, creatures that player controls can't attack you or planeswalkers you control until your next turn.

Defender When this creature enters, draw a card.

Equipped creature gets +4/+0. RW, Unattach this Equipment: Search your library for a red or white instant card with mana value 4 or less and cast that card without paying its mana cost. Then shuffle. Equip 3

Flying Whenever this creature deals combat damage to a player, each player discards their hand, then draws seven cards.

This land enters tapped unless you control a Swamp or a Mountain. T: Add B or R.