Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
This creature can't be blocked.

Distortion Strike

Target creature gets +1/+0 until end of turn and can't be blocked this turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Might of Old Krosa

Target creature gets +2/+2 until end of turn. If you cast this spell during your main phase, that creature gets +4/+4 until end of turn instead.

Groundswell

Target creature gets +2/+2 until end of turn.
Landfall — If you had a land enter the battlefield under your control this turn, that creature gets +4/+4 until end of turn instead.

Scale Up

Until end of turn, target creature you control becomes a green Wurm with base power and toughness 6/4.
Overload {4}{G}{G} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Glistener Elf

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
This creature can't be blocked except by creatures with flying or reach.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Forest

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Island

Vines of Vastwood

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Target creature can't be the target of spells or abilities your opponents control this turn. If this spell was kicked, that creature gets +4/+4 until end of turn.