Mox Sapphire

Island

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Sol Ring

Stasis

Players skip their untap steps.
At the beginning of your upkeep, sacrifice Stasis unless you pay {U}.

Counterspell

Time Elemental

When Time Elemental attacks or blocks, at end of combat, sacrifice it and it deals 5 damage to you.
{2}{U}{U}, {T}: Return target permanent that isn't enchanted to its owner's hand.

Underground Sea

Control Magic

Enchant creature
You control enchanted creature.

Mana Short

Tap all lands target player controls and that player loses all unspent mana.

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Recall

Discard X cards, then return a card from your graveyard to your hand for each card discarded this way. Exile Recall.

Time Walk

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Mishra's Factory

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Boomerang

Return target permanent to its owner's hand.

Ancestral Recall

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.