Littjara

When you planeswalk to Littjara and at the beginning of your upkeep, create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)
Whenever chaos ensues, choose a creature type. Put a +1/+1 counter on each creature you control of that type.

Strixhaven

Instant and sorcery spells players cast have demonstrate. (Whenever a player casts an instant or sorcery spell, they may copy it. If they do, they choose an opponent to also copy it. Players may choose new targets for their copies.)
Whenever chaos ensues, return up to one target instant or sorcery card from a graveyard to its owner's hand.

Myrel, Shield of Argive

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.
Whenever Myrel, Shield of Argive attacks, create X 1/1 colorless Soldier artifact creature tokens, where X is the number of Soldiers you control.