This spell can't be countered.

Flying, trample, protection from white and from blue

{R}: Akroma, Angel of Fury gets +1/+0 until end of turn.

Morph {3}{R}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Protection from white and from black

Whenever you cast a creature spell, put a +1/+1 counter on Animar, Soul of Elements.

Creature spells you cast cost {1} less to cast for each +1/+1 counter on Animar.

Whenever a permanent is turned face up, you may draw a card.

{U}, {T}: Add {C}{C}{C}.

{T}: Add one mana of any color in your commander's color identity.

Turn target creature with a morph ability face down.

Cycling {U} ({U}, Discard this card: Draw a card.)

Whenever you cast a creature spell, draw a card.

Morph {5}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Brine Elemental is turned face up, each opponent skips their next untap step.

Whenever Broodhatch Nantuko is dealt damage, you may create that many 1/1 green Insect creature tokens.

Morph {2}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Morph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Chromeshell Crab is turned face up, you may exchange control of target creature you control and target creature an opponent controls.

{T}: Add {G}.

Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Coral Trickster is turned face up, you may tap or untap target permanent.

Deathtouch

Whenever a permanent you control is turned face up, you may return Deathmist Raptor from your graveyard to the battlefield face up or face down.

Megamorph {4}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

Creatures with power less than Den Protector's power can't block it.

Megamorph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

When Den Protector is turned face up, return target card from your graveyard to your hand.

{T}: Counter target spell unless its controller pays {1}.

Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Face-down creature spells you cast cost {1} less to cast.

{U}, {T}: Target creature attacks target opponent this turn if able.

Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

{2}{R}, {T}: Destroy target nonbasic land.

Morph {R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Morph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Echo Tracer is turned face up, return target creature to its owner's hand.

Morph--Return two Islands you control to their owner's hand. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Fathom Seer is turned face up, draw two cards.

Damage that would reduce your life total to less than 1 reduces it to 1 instead.

Morph {R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Look at the top five cards of your library. Put any number of permanent cards from among them onto the battlefield and the rest into your hand. Exile Genesis Ultimatum.

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Hooded Hydra enters the battlefield with X +1/+1 counters on it.

When Hooded Hydra dies, create a 1/1 green Snake creature token for each +1/+1 counter on it.

Morph {3}{G}{G}

As Hooded Hydra is turned face up, put five +1/+1 counters on it.

Flying

Morph {1}{G}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Icefeather Aven is turned face up, you may return another target creature to its owner's hand.

{T}: Add {R}.

Face-down creatures get +1/+1.

{2}{U}: Turn target face-down creature face up.

As Ixidron enters the battlefield, turn all other nontoken creatures face down. (They're 2/2 creatures.)

Ixidron's power and toughness are each equal to the number of face-down creatures on the battlefield.

Morph {2}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Jeering Instigator is turned face up, if it's your turn, gain control of another target creature until end of turn. Untap that creature. It gains haste until end of turn.

When Kadena's Silencer is turned face up, counter all abilities your opponents control.

Megamorph {1}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

Morph {4}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Kheru Spellsnatcher is turned face up, counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard. You may cast that card without paying its mana cost for as long as it remains exiled.

{T}: Add {C}.

Morph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Master of the Veil is turned face up, you may turn target creature with a morph ability face down.

{3}{U}{U}: Turn Mischievous Quanar face down.

Morph {1}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Mischievous Quanar is turned face up, copy target instant or sorcery spell. You may choose new targets for that copy.

Morph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Nantuko Vigilante is turned face up, destroy target artifact or enchantment.

{T}: Add {C}{C}.

Whenever you cast a creature spell, you may draw a card.

{T}: Add {C}. Spend this mana only to cast a face-down creature spell, pay a mana cost to turn a manifested creature face up, or pay a morph cost. (A megamorph cost is a morph cost.)

{T}: Add {G}, {U}, or {R}.

Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Rattleclaw Mystic is turned face up, add {G}{U}{R}.

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Whenever Riptide Entrancer deals combat damage to a player, you may sacrifice it. If you do, gain control of target creature that player controls. (This effect lasts indefinitely.)

Morph {U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Trample, hexproof

Morph {3}{G}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

{T}: Manifest a card from your hand. (Put that card onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Face-down creatures you control get +0/+1.

Whenever a permanent you control is turned face up, draw a card.

Untap all permanents you control during each other player's untap step.

{T}: Add {U}.

Haste

{T}: Turn target face-down creature you control face up. At the beginning of the next end step, sacrifice it.

{T}: Add {C}{C}.

Trample

Whenever another nontoken creature enters the battlefield under your control, you may draw a card.

Flying

Megamorph {1}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

When Stratus Dancer is turned face up, counter target instant or sorcery spell.

All Saprolings get +1/+1.

Morph {3}{G}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Thelonite Hermit is turned face up, create four 1/1 green Saproling creature tokens.

Flying

Morph {5}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Thousand Winds is turned face up, return all other tapped creatures to their owners' hands.

{T}: Add {C}{C}{C}.

Whenever a face-down creature enters the battlefield under your control, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Whenever a permanent you control is turned face up, if it's a creature, it gets +2/+2 until end of turn.

Colorless spells you cast cost {2} less to cast.

+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.

-3: Destroy target permanent that's one or more colors.

Morph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Whenever Unblinking Bleb or another permanent is turned face up, you may scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

As Vesuvan Shapeshifter enters the battlefield or is turned face up, you may choose another creature on the battlefield. If you do, until Vesuvan Shapeshifter is turned face down, it becomes a copy of that creature, except it has "At the beginning of your upkeep, you may turn this creature face down."

Morph {1}{U}

You may cast creature spells as though they had flash.

+1: Until your next turn, up to one target creature gains vigilance and reach.

-2: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may look at that card and you may cast it if it's a creature spell.

Morph {2}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Voidmage Apprentice is turned face up, counter target spell.

{U}{U}, Sacrifice a Wizard: Counter target spell.

Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Morph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

When Weaver of Lies is turned face up, turn any number of target creatures with morph abilities other than Weaver of Lies face down.