Kashi-Tribe Reaver

Whenever Kashi-Tribe Reaver deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.
{1}{G}: Regenerate Kashi-Tribe Reaver.

Matsu-Tribe Decoy

{2}{G}: Target creature blocks Matsu-Tribe Decoy this turn if able.
Whenever Matsu-Tribe Decoy deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Thousand-legged Kami

Soulshift 7 (When this creature dies, you may return target Spirit card with mana value 7 or less from your graveyard to your hand.)

Venerable Kumo

Reach (This creature can block creatures with flying.)
Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Orochi Ranger

Whenever Orochi Ranger deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Wear Away

Destroy target artifact or enchantment.
Splice onto Arcane {3}{G} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Strength of Cedars

Target creature gets +X/+X until end of turn, where X is the number of lands you control.

Serpent Skin

Flash
Enchant creature
Enchanted creature gets +1/+1.
{G}: Regenerate enchanted creature.

Matsu-Tribe Sniper

{T}: Matsu-Tribe Sniper deals 1 damage to target creature with flying.
Whenever Matsu-Tribe Sniper deals damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Forest

Soilshaper

Whenever you cast a Spirit or Arcane spell, target land becomes a 3/3 creature until end of turn. It's still a land.

Sosuke, Son of Seshiro

Other Snake creatures you control get +1/+0.
Whenever a Warrior you control deals combat damage to a creature, destroy that creature at end of combat.

Orochi Sustainer

Sachi, Daughter of Seshiro

Other Snake creatures you control get +0/+1.
Shamans you control have "{T}: Add {G}{G}."

Orbweaver Kumo

Reach (This creature can block creatures with flying.)
Whenever you cast a Spirit or Arcane spell, Orbweaver Kumo gains forestwalk until end of turn. (It can't be blocked as long as defending player controls a Forest.)