Damnation

Destroy all creatures. They can't be regenerated.

Elesh Norn, Grand Cenobite

Vigilance
Other creatures you control get +2/+2.
Creatures your opponents control get -2/-2.

Urza's Rebuff

Choose one —
• Counter target spell.
• Tap up to two target creatures.

Tome Scour

Counterspell

Memnite

Dromar's Cavern

When Dromar's Cavern enters, sacrifice it unless you return a non-Lair land you control to its owner's hand.
{T}: Add {W}, {U}, or {B}.

Underground Sea

Urza, Lord High Artificer

When Urza, Lord High Artificer enters, create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

Propaganda

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

Tundra

Myrsmith

Whenever you cast an artifact spell, you may pay {1}. If you do, create a 1/1 colorless Myr artifact creature token.

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Spellskite

{U/P}: Change a target of target spell or ability to Spellskite. ({U/P} can be paid with either {U} or 2 life.)

Ancient Spring

Ancient Spring enters tapped.
{T}: Add {U}.
{T}, Sacrifice Ancient Spring: Add {W}{B}.

Prototype Portal

Imprint — When Prototype Portal enters, you may exile an artifact card from your hand.
{X}, {T}: Create a token that's a copy of the exiled card. X is the mana value of that card.

Raffine's Tower

({T}: Add {W}, {U}, or {B}.)
Raffine's Tower enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)