Boxing Day

At the beginning of the end step, if you control no artifacts, sacrifice Glimmervoid. {T}: Add one mana of any color.

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain. {T}: Add {B} or {R}.

{T}: Add {C}. {1}, {T}, Sacrifice Esper Panorama: Search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped...

Whenever a player casts a green spell, you may gain 1 life.

Farmstead Gleaner doesn't untap during your untap step. {2}, {Q}: Put a +1/+1 counter on Farmstead Gleaner. ({Q} is the untap symbol.)

Piranha Marsh enters the battlefield tapped. When Piranha Marsh enters the battlefield, target player loses 1 life. {T}: Add {B}.

{4}, {T}: Put a fate counter on target permanent. {5}, {T}, Sacrifice Oblivion Stone: Destroy each nonland permanent without a fate counter on it, ...

Whenever equipped creature deals combat damage to a player, destroy all permanents other than Worldslayer. Equip {5} ({5}: Attach to target creatur...

Dakmor Salvage enters the battlefield tapped. {T}: Add {B}. Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return t...

Galvanic Juggernaut attacks each combat if able. Galvanic Juggernaut doesn't untap during your untap step. Whenever another creature dies, untap ...

When Prophetic Prism enters the battlefield, draw a card. {1}, {T}: Add one mana of any color.

Equipped creature gets +3/+0 and attacks each combat if able. Equip {3}

Crumbling Necropolis enters the battlefield tapped. {T}: Add {U}, {B}, or {R}.

{3}, {T}, Sacrifice Gem of Becoming: Search your library for an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into y...

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.) When Crumbling Colossus attacks, sacrifice it ...

Whenever a player casts a black spell, you may gain 1 life.

Sunburst (This enters the battlefield with a charge counter on it for each color of mana spent to cast it.) {2}, Sacrifice Engineered Explosives: D...

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

{U}: Untap Soliton.

Chimeric Mass enters the battlefield with X charge counters on it. {1}: Until end of turn, Chimeric Mass becomes a Construct artifact creature wit...

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

Metalcraft — Snapsail Glider has flying as long as you control three or more artifacts.

{3}, {T}: Tap target creature. Gain control of that creature instead if you control artifacts named Scepter of Empires and Throne of Empires.