Ygra, Eater of All

Ward—Sacrifice a Food.
Other creatures are Food artifacts in addition to their other types and have "{2}, {T}, Sacrifice this permanent: You gain 3 life."
Whenever a Food is put into a graveyard from the battlefield, put two +1/+1 counters on Ygra, Eater of All.

Seeds of Innocence

Destroy all artifacts. They can't be regenerated. The controller of each of those artifacts gains life equal to its mana value.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Collector Ouphe

Activated abilities of artifacts can't be activated.

Ashnod's Altar

Bane of Progress

When Bane of Progress enters, destroy all artifacts and enchantments. Put a +1/+1 counter on Bane of Progress for each permanent destroyed this way.

Camellia, the Seedmiser

Menace
Other Squirrels you control have menace.
Whenever you sacrifice one or more Foods, create a 1/1 green Squirrel creature token.
{2}, Forage: Put a +1/+1 counter on each other Squirrel you control. (To forage, exile three cards from your graveyard or sacrifice a Food.)