Vorinclex, Voice of Hunger

Trample
Whenever you tap a land for mana, add one mana of any type that land produced.
Whenever an opponent taps a land for mana, that land doesn't untap during its controller's next untap step.

Necron Overlord

Relentless March — {X}, {T}, Tap X untapped artifacts you control: Target opponent loses X life.

Ghirapur Aether Grid

Tap two untapped artifacts you control: This enchantment deals 1 damage to any target.

Vazi, Keen Negotiator

Haste
{T}: Target opponent creates X Treasure tokens, where X is the number of Treasure tokens you created this turn.
Whenever an opponent casts a spell or activates an ability, if mana from a Treasure was spent to cast it or activate it, put a +1/+1 counter on target creature, then draw a card.

Network Terminal

{T}: Add one mana of any color.
{1}, {T}, Tap another untapped artifact you control: Draw a card, then discard 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.

Citanul Stalwart

{T}, Tap an untapped artifact or creature you control: Add one mana of any color.

Rakdos, Patron of Chaos

Flying, trample
At the beginning of your end step, target opponent may sacrifice two nonland, nontoken permanents of their choice. If they don't, you draw two cards.

Winter Orb

As long as this artifact is untapped, players can't untap more than one land during their untap steps.

Worms of the Earth

Players can't play lands.
Lands can't enter the battlefield.
At the beginning of each upkeep, any player may sacrifice two lands of their choice or have this enchantment deal 5 damage to that player. If a player does either, destroy this enchantment.