Ghoulcaller's Bell

Mesmeric Orb

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

Grindstone

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

Keening Stone

{5}, {T}: Target player mills X cards, where X is the number of cards in that player's graveyard.

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Folio of Fancies

Players have no maximum hand size.
{X}{X}, {T}: Each player draws X cards.
{2}{U}, {T}: Each opponent mills cards equal to the number of cards in their hand.