Flying

When this creature enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

When this creature enters, it deals 1 damage to each opponent. Create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")

Mutate {1}{R/W}{R/W} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Whenever this creature mutates, other creatures you control get +2/+1 until end of turn.

Haste (This creature can attack and {T} as soon as it comes under your control.) Whenever this creature attacks, other creatures you control get +1/+0 until end of turn.

Convoke When this creature enters, look at the top six cards of your library. You may reveal up to two creature cards with mana value X or less from among them, where X is the number of creatures that convoked this creature. Put the revealed cards into your hand, then shuffle.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) When this creature enters, put a +1/+1 counter on each creature that convoked it.

(Gain the next level as a sorcery to add its ability.) Spells your opponents cast during your turn cost {1} more to cast. {2}{W}: Level 2 Creatures you control get +1/+1. {4}{W}: Level 3 Whenever you attack, until end of turn, target attacking creature gets +1/+1 for each other attacking creature and gains double strike.

Destroy target artifact. If you controlled that artifact, create three 1/1 red Phyrexian Goblin creature tokens.

Create a 1/1 red Dinosaur creature token with haste and a 1/1 white Human Soldier creature token.

This land enters tapped unless you control a Plains. {T}: Add {W}. {2}{W}{W}, {T}: Create a 1/1 white Human creature token.

({T}: Add {W}.)

This land enters tapped unless you control a Mountain. {T}: Add {R}. {1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

If you control two or more other lands, this land enters tapped. {T}: Add {R}. {3}{R}: Until end of turn, this land becomes a 3/2 red Goblin creature with "Whenever this creature attacks, create a 1/1 red Goblin creature token that's tapped and attacking." It's still a land.

({T}: Add {R}.)

{T}: Add {C}. {T}: Add {R} or {W}. This land deals 1 damage to you.

({T}: Add {R} or {W}.) As this land enters, you may pay 2 life. If you don't, it enters tapped.