Zodiac Rabbit

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)

Copy

(This token can be used to represent a token that's a copy of a permanent.)

Placid Rottentail

Vigilance
{2}{G}, Exile Placid Rottentail from your graveyard: Put two +1/+1 counters on target creature. Activate only as a sorcery.

Mouse

Three Blind Mice

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I — Create a 1/1 white Mouse creature token.
II, III — Create a token that's a copy of target token you control.
IV — Creatures you control get +1/+1 and gain vigilance until end of turn.

Calix, Guided by Fate

Constellation — Whenever Calix, Guided by Fate or another enchantment you control enters, put a +1/+1 counter on target creature.
Whenever Calix or an enchanted creature you control deals combat damage to a player, you may create a token that's a copy of a nonlegendary enchantment you control. Do this only once each turn.

Preston, the Vanisher

Whenever another nontoken creature you control enters, if it wasn't cast, create a token that's a copy of that creature, except it's a 0/1 white Illusion.
{1}{W}, Sacrifice five Illusions: Exile target nonland permanent.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Hare Raising

Target creature you control gains vigilance and gets +X/+X until end of turn, where X is the number of creatures you control.

Pollen-Shield Hare

Pollen-Shield Hare // Hare Raising

Cadira, Caller of the Small

Trample
Whenever Cadira, Caller of the Small deals combat damage to a player, for each token you control, create a 1/1 white Rabbit creature token.

Regal Bunnicorn

Regal Bunnicorn's power and toughness are each equal to the number of nonland permanents you control.

Nurturing Presence

Enchant creature
Enchanted creature has "Whenever a creature you control enters, this creature gets +1/+1 until end of turn."
When Nurturing Presence enters, create a 1/1 white Spirit creature token with flying.