Have

Ghoulcaller's Bell

Grindstone

{3}, {T}: Target player mills two cards. If two cards that share a color were milled this way, repeat this process.

Sands of Delirium

Painter's Servant

As this creature enters, choose a color.
All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

Don't Have

Roxanne, Starfall Savant

Whenever Roxanne enters or attacks, create a tapped colorless artifact token named Meteorite with "When this token enters, it deals 2 damage to any target" and "{T}: Add one mana of any color."
Whenever you tap an artifact token for mana, add one mana of any type that artifact token produced.

Sarinth Greatwurm

Trample
Whenever a land enters, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Meria, Scholar of Antiquity

Tap an untapped nontoken artifact you control: Add {G}.
Tap two untapped nontoken artifacts you control: Exile the top card of your library. You may play it this turn.

Kurkesh, Onakke Ancient

Whenever you activate an ability of an artifact, if it isn't a mana ability, you may pay {R}. If you do, copy that ability. You may choose new targets for the copy.

Grindclock

{T}: Put a charge counter on this artifact.
{T}: Target player mills X cards, where X is the number of charge counters on this artifact.