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.)
Blighted Agent can't be blocked.

Spell Pierce

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

Mammoth Growth

Target creature gets +4/+4 until end of turn.
Foretell {G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Titanic Growth

Target creature gets +4/+4 until end of turn.

Forest

Predator's Strike

Target creature gets +3/+3 and gains trample until end of turn.

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Island

Serpentine Ambush

Until end of turn, target creature becomes a blue Serpent with base power and toughness 5/5.

Bombadil's Song

Target creature you control gets +1/+1 and gains hexproof until end of turn. The Ring tempts you. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Mortal's Resolve

Target creature gets +1/+1 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Ichorclaw Myr becomes blocked, it gets +2/+2 until end of turn.

Phytoburst

Target creature gets +5/+5 until end of turn.

Blight Mamba

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{1}{G}: Regenerate Blight Mamba.

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.)