Kharis & The Beholder

Flying
When Kharis & The Beholder enters the battlefield and at the beginning of your upkeep, create a 1/1 white Human creature token and make a charisma check. (Roll a d20.)
• If the result plus the number of creatures you control is greater than 11, put a +1/+1 counter on each creature you control.
• If the result is a natural 20, for each nonlegendary creature you control, create a token that's a copy of that creature.

Tamiyo's Immobilizer

Tamiyo's Immobilizer enters the battlefield with four oil counters on it.
{T}, Remove an oil counter from Tamiyo's Immobilizer: Tap target artifact or creature.

Awaken the Sleeper

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If it's equipped, you may destroy all Equipment attached to that creature.

Reject Imperfection

Counter target spell. If that spell's mana value was 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Forest

Lattice-Blade Mantis

Lattice-Blade Mantis enters the battlefield with two oil counters on it.
Whenever Lattice-Blade Mantis attacks, you may remove an oil counter from it. If you do, untap it and it gets +1/+1 until end of turn.

Copper Longlegs

Reach
{1}{G}, Sacrifice Copper Longlegs: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sawblade Scamp

Haste
Whenever you cast a noncreature spell, put an oil counter on Sawblade Scamp.
{T}, Remove an oil counter from Sawblade Scamp: It deals 1 damage to each opponent.

Urabrask's Anointer

When Urabrask's Anointer enters the battlefield, it deals X damage to any target, where X is the number of permanents you control with oil counters on them.

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Resistance Reunited

Target creature gets +2/+2 until end of turn.
Equipped creatures you control gain indestructible until end of turn.

Tyrranax Rex

This spell can't be countered.
Trample, ward {4}, haste
Toxic 4 (Players dealt combat damage by this creature also get four poison counters.)

Meldweb Strider

Vigilance
Meldweb Strider enters the battlefield with an oil counter on it.
Remove an oil counter from Meldweb Strider: It becomes an artifact creature until end of turn.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)