First Day of Class

Whenever a creature you control enters this turn, put a +1/+1 counter on it and it gains haste until end of turn.
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)

Forge of Heroes

{T}: Add {C}.
{T}: Choose target commander that entered this turn. Put a +1/+1 counter on it if it's a creature and a loyalty counter on it if it's a planeswalker.

Reckoner Shakedown

Target opponent reveals their hand. You may choose a nonland card from it. If you do, that player discards that card. If you don't, put two +1/+1 counters on a creature or Vehicle you control.

Subtle Strike

Choose one or both —
• Target creature gets -1/-1 until end of turn.
• Put a +1/+1 counter on target creature.

Expanded Anatomy

Put two +1/+1 counters on target creature. It gains vigilance until end of turn.

Chainbreaker

Chainbreaker enters with two -1/-1 counters on it.
{3}, {T}: Remove a -1/-1 counter from target creature.

Sparring Construct

When Sparring Construct dies, put a +1/+1 counter on target creature you control.

Viscera Seer

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

Explosive Entry

Destroy up to one target artifact. Put a +1/+1 counter on up to one target creature.

Murderous Redcap

When Murderous Redcap enters, it deals damage equal to its power to any target.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Essence Infusion

Put two +1/+1 counters on target creature. It gains lifelink until end of turn.

Myr Scrapling

Sacrifice Myr Scrapling: Put a +1/+1 counter on target creature.

Spinal Centipede

When Spinal Centipede dies, put a +1/+1 counter on target creature you control.

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

Professor's Warning

Choose one —
• Put a +1/+1 counter on target creature.
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Novice Dissector

{1}, Sacrifice another creature: Put a +1/+1 counter on target creature. Activate only as a sorcery.

Blood Aspirant

Whenever you sacrifice a permanent, put a +1/+1 counter on Blood Aspirant.
{1}{R}, {T}, Sacrifice a creature or enchantment: Blood Aspirant deals 1 damage to target creature. That creature can't block this turn.

Cannibalize

Choose two target creatures controlled by the same player. Exile one of those creatures and put two +1/+1 counters on the other.

Weapon Rack

Weapon Rack enters with three +1/+1 counters on it.
{T}: Move a +1/+1 counter from Weapon Rack onto target creature. Activate only as a sorcery.

Goblin Assault Team

Haste
When Goblin Assault Team dies, put a +1/+1 counter on target creature you control.

Wither and Bloom

Target creature gets -3/-3 until end of turn.
{1}{B}, Exile Wither and Bloom from your graveyard: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Putrid Goblin

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Iron Apprentice

Iron Apprentice enters with a +1/+1 counter on it.
When Iron Apprentice dies, if it had counters on it, put those counters on target creature you control.