River Bear

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Bear Cub

Crown of Suspicion

Enchant creature
Enchanted creature gets +2/-1.
Sacrifice Crown of Suspicion: Enchanted creature and other creatures that share a creature type with it get +2/-1 until end of turn.

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.

Runeclaw Bear

Dragon-Scarred Bear

Formidable — {1}{G}: Regenerate Dragon-Scarred Bear. Activate only if creatures you control have total power 8 or greater.

Forebear's Blade

Equipped creature gets +3/+0 and has vigilance and trample.
Whenever equipped creature dies, attach Forebear's Blade to target creature you control.
Equip {3}

Haunted One

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Owlbear

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

Mother Bear

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

Alpha Status

Enchant creature
Enchanted creature gets +2/+2 for each other creature on the battlefield that shares a creature type with it.

Ashcoat Bear

Flash (You may cast this spell any time you could cast an instant.)

Striped Bears

Exuberant Wolfbear

Whenever Exuberant Wolfbear attacks, you may change the base power and toughness of target Human you control to Exuberant Wolfbear's power and toughness until end of turn.

Razorclaw Bear

Whenever Razorclaw Bear becomes blocked, it gets +2/+2 until end of turn.

Owlbear Shepherd

At the beginning of your end step, if creatures you control have total power 8 or greater, draw a card.

Ulvenwald Bear

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

Stuffed Bear

{2}: Stuffed Bear becomes a 4/4 green Bear artifact creature until end of turn.

Bear Umbra

Enchant creature
Enchanted creature gets +2/+2 and has "Whenever this creature attacks, untap all lands you control."
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Wilson, Refined Grizzly

This spell can't be countered.
Vigilance, reach, trample
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Choose a Background (You can have a Background as a second commander.)

Balduvian Bears

Call of the Wild

{2}{G}{G}: Reveal the top card of your library. If it's a creature card, put it onto the battlefield. Otherwise, put it into your graveyard.

Bearscape

{1}{G}, Exile two cards from your graveyard: Create a 2/2 green Bear creature token.

Forest Bear

Owlbear Cub

Mama's Coming — Whenever Owlbear Cub attacks a player who controls eight or more lands, look at the top eight cards of your library. You may put a creature card from among them onto the battlefield tapped and attacking that player. Put the rest on the bottom of your library in a random order.

Belbe's Portal

As Belbe's Portal enters, choose a creature type.
{3}, {T}: You may put a creature card of the chosen type from your hand onto the battlefield.

Aphetto Dredging

Return up to three target creature cards of the creature type of your choice from your graveyard to your hand.

Spectral Bears

Whenever Spectral Bears attacks, if defending player controls no black nontoken permanents, it doesn't untap during your next untap step.

Crown of Vigor

Enchant creature
Enchanted creature gets +1/+1.
Sacrifice Crown of Vigor: Enchanted creature and other creatures that share a creature type with it get +1/+1 until end of turn.

Pale Bears

Grizzly Bears

Crippling Fear

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

Werebear

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