When this creature enters, suspect it. Create a 2/2 white and blue Detective creature token. (A suspected creature has menace and can't block.)

This creature gets +2/+0 as long as it isn't attacking or blocking.

Put target creature on the bottom of its owner's library. You lose 2 life unless you control a Villain.

Each other creature you control that's a Fungus or Saproling gets +1/+1.

(Gain the next level as a sorcery to add its ability.)
When this Class enters, each player creates a Food token.
: Level 2
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, draw a card.
: Level 3
Whenever one or more of your opponents are attacked, up to one target attacking creature gets +X/+X until end of turn, where X is the number of cards in your hand.

Trample
Forestcycling (, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

: Add .
, : Exile target creature you own.
, , Sacrifice this land: Return a creature card exiled with this land to the battlefield under your control. Return each other card exiled with this land to its owner's hand.

This spell costs less to cast if you control a creature with flying.
Return target nonland permanent you don't control to its owner's hand.
Draw a card.

This spell costs less to cast if it targets a tapped creature.
Destroy target creature.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

At the beginning of combat on your turn, target creature you control gets +1/+0 and gains first strike until end of turn.

Vigilance
: Put a +1/+1 counter on each other Hero you control.

Return up to one target permanent card from your graveyard to your hand.
Create a Clue token. (It's an artifact with ", Sacrifice this token: Draw a card.")

Prowler can't be blocked by creatures with power 2 or less.
Whenever Prowler deals combat damage to a player, put a +1/+1 counter on another target creature you control.

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

This spell costs less to cast if a creature card was put into your graveyard from anywhere this turn.
Return up to two target creature cards from your graveyard to your hand.

When this creature enters, investigate. (Create a Clue token. It's an artifact with ", Sacrifice this token: Draw a card.")
Whenever you draw your second card each turn, this creature gets +1/+1 and gains vigilance until end of turn.

: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

When this artifact enters, it deals 4 damage to any target and 3 damage to you.
, , Sacrifice this artifact: You gain 3 life.

Create a 3/3 blue and red Elemental creature token with flying.
Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)