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.

The Filigree Sylex

{T}: Put an oil counter on The Filigree Sylex.
{T}, Sacrifice The Filigree Sylex: Destroy each nonland permanent with mana value equal to the number of oil counters on The Filigree Sylex.
{T}, Remove ten oil counters from among permanents you control and sacrifice The Filigree Sylex: It deals 10 damage to any target.

Vorel of the Hull Clade

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

Lux Artillery

Whenever you cast an artifact creature spell, it gains sunburst. (It enters with a +1/+1 counter on it for each color of mana spent to cast it.)
At the beginning of your end step, if there are thirty or more counters among artifacts and creatures you control, Lux Artillery deals 10 damage to each opponent.

The Millennium Calendar

Whenever you untap one or more permanents during your untap step, put that many time counters on The Millennium Calendar.
{2}, {T}: Double the number of time counters on The Millennium Calendar.
When there are 1,000 or more time counters on The Millennium Calendar, sacrifice it and each opponent loses 1,000 life.

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.

Migloz, Maze Crusher

Migloz, Maze Crusher enters with five oil counters on it.
{1}, Remove an oil counter from Migloz: It gains vigilance and menace until end of turn.
{2}, Remove two oil counters from Migloz: It gets +2/+2 until end of turn.
{3}, Remove three oil counters from Migloz: Destroy target artifact or enchantment.