Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Tree of Tales

Ancient Den

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Lotus Field

Hexproof
Lotus Field enters tapped.
When Lotus Field enters, sacrifice two lands.
{T}: Add three mana of any one color.

Vault of Whispers

Great Furnace

Planar Bridge

{8}, {T}: Search your library for a permanent card, put it onto the battlefield, then shuffle.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Ornithopter

Kuldotha Forgemaster

{T}, Sacrifice three artifacts: Search your library for an artifact card, put it onto the battlefield, then shuffle.

Seat of the Synod

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Mishra's Bauble

{T}, Sacrifice Mishra's Bauble: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Blightsteel Colossus

Trample, infect, indestructible
If Blightsteel Colossus would be put into a graveyard from anywhere, reveal Blightsteel Colossus and shuffle it into its owner's library instead.