Whenever you cast a spell from your graveyard, each opponent loses 1 life and you gain 1 life.
Surface {3}{B}{B}. Chum Chaser surfaces transformed.

Whenever you attack, put a +1/+1 counter on a creature you control.

When Cliffside Scrappers enters, destroy target artifact an opponent controls.
Wander {3}{R}{R}

Choose one —
• Destroy target artifact or enchantment.
• Return target permanent card from your graveyard to your hand.

Drop — When Club Promoter enters, choose one. If you didn't cast any creature spells during your last turn, you may choose both instead.
• Destroy target artifact or enchantment.
• Put two +1/+1 counters on Club Promoter.

When Codename: Spyder enters, mill three cards.
Whenever one or more cards are put into your graveyard from your library, you may return up to one of those cards to your hand. Do this only once each turn.

When Coercive Contractor enters, create a Treasure token.
{X}, {T}, Sacrifice a Treasure: Gain control of target nontoken creature with mana value X until end of turn. Untap that creature. It gains haste until end of turn. Activate only as a sorcery.

Create a 0/0 white Army creature token if your devotion to white is three or more.
Put a +1/+1 counter on each creature you control.

Whenever a creature you control becomes the target of a spell or ability that targets only it, you may copy that spell or ability for each other creature you control that spell or ability could target. Each copy targets a different one of those creatures. Do this only once each turn.

Gain control of up to two target creatures with total mana value 4 or less until end of turn. Untap one of them. It gains haste until end of turn.

Counter target activated ability from a nonland source.
Draw a card.

Enchant creature
Enchanted creature gets +1/+1 and has “Whenever this creature deals combat damage to a player, draw a card.”
{VP}{VP}{VP}: Enchanted creature gains flying until end of turn.

When Contest Coordinator enters, look at the top five cards of your library. You may reveal a Plains card or a nonland card with an activated ability from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Once each turn, when you activate an ability of a creature you control, untap that creature and put a +1/+1 counter on it.

{T}, Tap another untapped creature you control: You may tap or untap another target creature.
Whenever Contest Star becomes untapped, draw a card.

Corgan Bourgeois's power is equal to the number of artifacts you control.
Whenever Corgan Bourgeois or another artifact you control enters, you gain 1 life.

Whenever a creature dies, scry 1.

Whenever a creature you control deals combat damage to a player, you may sacrifice it. If you do, draw a card. Otherwise, surveil 1.

Menace
Whenever Corporate Mentor attacks, teach target attacking creature with lesser power menace.

Flash
When Corrosive Spitter enters, destroy all creatures that were dealt damage this turn.

When Cosmic Colossus enters, if you cast it from your hand, cast a copy of target card in exile without paying its mana cost unless an opponent exiles two nonland permanents they control.

{T}: Add {C}.
{1}, {T}, Sacrifice Cradle of Rebirth: Copy target spell you control which had its flashback cost paid. You may choose new targets for the copy.

Vigilance
Whenever this creature transforms into Crown Betrayer or another permanent you control transforms, Crown Betrayer gets +2/+0 and gains indestructible until end of turn.

Cruiser Technician can't be blocked except by artifact creatures.
Whenever you amp it up, draw two cards, then discard two cards.

Landfall — Whenever a land you control enters, exile the top card of your library. You may play that card until the end of your next turn.
{1}{R}, Sacrifice Crumbling Tower: It deals damage equal to the number of cards exiled with it to target player.