Flickerwisp

Flying
When this creature enters, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is this creature's power.

Stasis Snare

Flash (You may cast this spell any time you could cast an instant.)
When this enchantment enters, exile target creature an opponent controls until this enchantment leaves the battlefield.

Soul Warden

Whenever another creature enters, you gain 1 life.

Springjack Shepherd

Chroma — When this creature enters, create a 0/1 white Goat creature token for each white mana symbol in the mana costs of permanents you control.

Thistledown Liege

Flash
Other white creatures you control get +1/+1.
Other blue creatures you control get +1/+1.

Mirrorweave

Each other creature becomes a copy of target nonlegendary creature until end of turn.

Knight of the White Orchid

First strike
When this creature enters, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Elesh Norn, Grand Cenobite

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