This land enters tapped. As it enters, choose a color.
When this land enters, return a land you control to its owner's hand.
{T}: Add {C} and one mana of the chosen color.

Enchant creature you control
Enchanted creature gets +1/+1.
When this Aura enters, enchanted creature fights up to one target creature.

When Cliffwalker enters, return a permanent you control to its owner's hand.
Wander {1}{W}

When Seafloor Scavenger enters or deals combat damage to a player, you may return target exiled card with surface you own to your hand.

Revered
Whenever this creature attacks, creatures you control get +1/+0 until end of turn.

Equipped creature gets +3/+1.
Whenever a Ruin you control becomes spellcharged, you may attach Landmark Blade to it.
Equip {3}

Corrupt — When this creature enters, if it isn't a token and you control a permanent with greater mana value than it, create a token that's a copy of this creature.
{T}: Add {G}.

This spell can't be countered.
First strike, haste
Whenever an opponent casts a spell during your turn, End of Mutations deals 5 damage to them.

When this creature enters, search your library for a basic land card, cache it, then shuffle.

{2}{U}, {T}: Draw a card.
{6}{U}{U}, {T}: Draw four cards.

Vigilance, ward {1}
Whenever Lio or another enchantment creature you control enters, put a +1/+1 counter on that creature. You gain 1 life and draw a card.

Whenever this creature attacks, exile up to one target creature card with mana value equal to 1 plus this creature's mana value from your graveyard. This creature becomes a copy of that card, except it has this ability.

Flash
Ward {3}
You may reveal the second card you draw each turn as you draw it. When you do, you may cast it without paying its mana cost. If you didn't cast a spell this way, create two Treasure tokens.

{3}{R}: Exile the top card of your library. You may play that card until the end of your next turn.
{7}{R}: Exotic Transformer deals damage equal to its power to any target.

Controlled Ecosystem enters tapped.
{T}: Add {G} or {U}.
{4}: Make a pledge. Activate only as a sorcery.

Destroy target creature if its mana value is less than or equal to the amount of mana spent to cast this spell.
Flashback {X}{B}{B}{B}

Creatures you control get +X/+X and gain vigilance and trample until end of turn, where X is the number of Forests you control plus the number of cards with a cycling ability in your graveyard.
Forestcycling {2}

When this creature enters, create a blue Subroutine enchantment token named READ with “Whenever this Subroutine runs, draw a card.”

Whenever you gain life, you may create a 0/0 colorless Robot artifact creature token with X +1/+1 counters on it, where X is the amount of life you gained. Do this only once each turn.

Flying
Amity — Whenever you attack with Fluttering Firefly and exactly one other creature, target creature you control gets +2/+0 until end of turn.

When Alrantan Visionary enters, reveal the top three cards of your library. Put a noncreature permanent card from among them into your hand and the rest into your graveyard.
{T}: Add one mana of any color.
Wander {4}{G}{G}

{T}: Add {C}.
If a spell or ability you control would produce {C}, you may pay 1 life. If you do, it produces {U} instead.

{T}: Target player exiles a card from their graveyard.
{2}, {T}: Exile target card from a graveyard. Then if there are three or more cards exiled with Censor Tablet, exile it. If you do, draw two cards.

Whenever you cast a green spell, choose up to X, where X is the number of green mana symbols in that spell's mana cost —
• Create a 1/1 white Human creature token.
• Put a +1/+1 counter on a creature you control.
• Put a trample counter, vigilance counter, or a reach counter on a creature you control.
• Untap target land.

Flash
When Narzi, Hero of the Mokar enters, up to one other target creature gets +1/+1 and gains indestructible until end of turn. If she wandered, other creatures you control get +1/+1 and gain indestructible until end of turn instead.
Wander {4}{W}{W}