Ichorplate Golem

Whenever a creature you control enters, if it has one or more oil counters on it, put an oil counter on it.
Creatures you control with oil counters on them get +1/+1.

Armored Scrapgorger

Armored Scrapgorger gets +3/+0 as long as it has three or more oil counters on it.
{T}: Add one mana of any color.
Whenever Armored Scrapgorger becomes tapped, exile target card from a graveyard and put an oil counter on Armored Scrapgorger.

Evolving Adaptive

Evolving Adaptive enters with an oil counter on it.
Evolving Adaptive gets +1/+1 for each oil counter on it.
Whenever another creature you control enters, if that creature has greater power or toughness than Evolving Adaptive, put an oil counter on Evolving Adaptive.

Urabrask's Anointer

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

Forest

Furnace Strider

Furnace Strider enters with two oil counters on it.
Remove an oil counter from Furnace Strider: Target creature you control gains haste until end of turn.

Churning Reservoir

At the beginning of your upkeep, put an oil counter on another target nontoken artifact or creature you control.
{2}, {T}: Create a 1/1 red Phyrexian Goblin creature token. Activate only if an oil counter was removed from a permanent you controlled this turn or a permanent with an oil counter on it was put into a graveyard this turn.

Volt Charge

Volt Charge deals 3 damage to any target. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Cinderslash Ravager

This spell costs {1} less to cast for each permanent you control with oil counters on it.
Vigilance
When Cinderslash Ravager enters, it deals 1 damage to each creature your opponents control.

Free from Flesh

Target creature gets +2/+2 until end of turn. Put two oil counters on it.

Axiom Engraver

Axiom Engraver enters with two oil counters on it.
{T}, Remove an oil counter from Axiom Engraver, Discard a card: Draw a card.

Lattice-Blade Mantis

Lattice-Blade Mantis enters 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.

Rustvine Cultivator

{T}: Put an oil counter on Rustvine Cultivator.
{T}, Remove an oil counter from Rustvine Cultivator: Untap target land.