Fungal Infection

Target creature gets -1/-1 until end of turn. Create a 1/1 green Saproling creature token.

Bloodsky Berserker

Whenever you cast your second spell each turn, put two +1/+1 counters on this creature. It gains menace until end of turn. (It can't be blocked except by two or more creatures.)

Disembowel

Destroy target creature with mana value X.

Lash of Malice

Target creature gets +2/-2 until end of turn.

Dark Betrayal

Nightmare's Thirst

You gain 1 life. Target creature gets -X/-X until end of turn, where X is the amount of life you gained this turn.

Lash of Thorns

Target creature gets +2/+1 and gains deathtouch until end of turn.

Ghastly Demise

Destroy target nonblack creature if its toughness is less than or equal to the number of cards in your graveyard.

Necrotic Wound

Undergrowth — Target creature gets -X/-X until end of turn, where X is the number of creature cards in your graveyard. If that creature would die this turn, exile it instead.

Profane Insight

You draw a card and you lose 1 life. (Then exile this card. You may cast the creature later from exile.)

Foulmire Knight

Foulmire Knight // Profane Insight

Eye Gouge

Target creature gets -1/-1 until end of turn. If it's a Cyclops, destroy it.

Marsh Gas

All creatures get -2/-0 until end of turn.

Cruel Feeding

Strive — This spell costs {2}{B} more to cast for each target beyond the first.
Any number of target creatures each get +1/+0 and gain lifelink until end of turn. (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Boon of Erebos

Target creature gets +2/+0 until end of turn. Regenerate it. You lose 2 life.

Cremate

Exile target card from a graveyard.
Draw a card.

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.)