Professor of Zoomancy

When Professor of Zoomancy enters, create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."

Grizzly Fate

Create two 2/2 green Bear creature tokens.
Threshold — Create four 2/2 green Bear creature tokens instead if seven or more cards are in your graveyard.
Flashback {5}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Spirit of the Aldergard

When Spirit of the Aldergard enters, search your library for a snow land card, reveal it, put it into your hand, then shuffle.
Spirit of the Aldergard gets +1/+0 for each other snow permanent you control.

Snow-Covered Forest

Owlbear

Trample
Keen Senses — When Owlbear enters, draw a card.

Shimmerdrift Vale

Shimmerdrift Vale enters tapped.
As Shimmerdrift Vale enters, choose a color.
{T}: Add one mana of the chosen color.

Blizzard Brawl

Choose target creature you control and target creature you don't control. If you control three or more snow permanents, the creature you control gets +1/+0 and gains indestructible until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Ayula, Queen Among Bears

Whenever another Bear you control enters, choose one —
• Put two +1/+1 counters on target Bear.
• Target Bear you control fights target creature you don't control.

Werebear

{T}: Add {G}.
Threshold — Werebear gets +3/+3 as long as seven or more cards are in your graveyard.

Mother Bear

{3}{G}{G}, Exile Mother Bear from your graveyard: Create two 2/2 green Bear creature tokens. Activate only as a sorcery.

Savage Swipe

Target creature you control gets +2/+2 until end of turn if its power is 2. Then it fights target creature you don't control. (Each deals damage equal to its power to the other.)

Ulvenwald Bear

Morbid — When Ulvenwald Bear enters, if a creature died this turn, put two +1/+1 counters on target creature.