Scoria Cat

This creature gets +3/+3 as long as you control no untapped lands.

Trumpet Blast

Attacking creatures get +2/+0 until end of turn.

Keldon Berserker

Whenever this creature attacks, if you control no untapped lands, it gets +3/+0 until end of turn.

Well of Discovery

At the beginning of your end step, if you control no untapped lands, draw a card.

Mountain

Manabarbs

Whenever a player taps a land for mana, this enchantment deals 1 damage to that player.

Citadel of Pain

At the beginning of each player's end step, this enchantment deals X damage to that player, where X is the number of untapped lands they control.

Branded Brawlers

This creature can't attack if defending player controls an untapped land.
This creature can't block if you control an untapped land.

Latulla, Keldon Overseer

{X}{R}, {T}, Discard two cards: Latulla deals X damage to any target.

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, this creature deals 2 damage to that player.

Chimeric Idol

{0}: Tap all lands you control. This artifact becomes a 3/3 Turtle artifact creature until end of turn.

Blood Moon

Shiv's Embrace

Enchant creature
Enchanted creature gets +2/+2 and has flying.
{R}: Enchanted creature gets +1/+0 until end of turn.

Well of Life

At the beginning of your end step, if you control no untapped lands, you gain 2 life.