Kudo, King Among Bears

Other creatures have base power and toughness 2/2 and are Bears in addition to their other types.

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.

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on this enchantment.
As long as this enchantment has seven or more quest counters on it, creatures you control get +5/+5.

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Sol Ring

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Elesh Norn, Grand Cenobite

Vigilance
Other creatures you control get +2/+2.
Creatures your opponents control get -2/-2.