Walking Ballista enters with X +1/+1 counters on it.: Put a +1/+1 counter on Walking Ballista.Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.
When Tenacious Pup enters the battlefield, you gain 1 life. You get a one-time boon with "When you cast a creature spell, that creature enters with an additional +1/+1 counter, trample counter, and vigilance counter on it."
As an additional cost to cast this spell, sacrifice a green creature.Search your library for a green creature card, put it onto the battlefield, then shuffle.
At the beginning of your upkeep, sacrifice Contamination unless you sacrifice a creature.If a land is tapped for mana, it produces instead of any other type and amount.
Xantcha, Sleeper Agent enters under the control of an opponent of your choice.Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.
First strikeWhenever Mirri, Weatherlight Duelist attacks, each opponent can't block with more than one creature this combat.As long as Mirri, Weatherlight Duelist is tapped, no more than one creature can attack you each combat.
Karn, Legacy Reforged's power and toughness are each equal to the greatest mana value among artifacts you control.At the beginning of your upkeep, add for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.
