When a unit goes to your void while Uxu is in your deck, Uxu gets +5/-1, +3 Strength, +3 Health, -1/+5,
Aegis,
Berserk,
Deadly,
Decay,
Killer,
Lifesteal,
Overwhelm,
Quickdraw, or
Ambush.
Card sounds may differ from in-game as they get updated.
Aegis - Aegis protects a unit or player from one enemy spell or effect. It doesn't block friendly effects, nor does it stop battle damage from Killer attacks, Relic Weapons, or normal attacking and blocking.
Ambush - An ambush unit can be played at the end of the enemy player's turn, or any time they are attacking you. If you played against a Killer or Relic Weapon attack, an Ambush unit will jump in the way to block that attack.
Deadly - Units and spells with Deadly kill any unit they damage, regardless of health. For example, a 1/1 with Deadly can kill a 5/5 attacker.
Killer - A unit with Killer can make one special attack directly against an enemy unit. This can be done the turn it's played, and can target any unit, regardless of Flying, Aegis, or other special abilities.
Lifesteal - Units and spells with Lifesteal give you health when they deal damage, healing you equal to the damage dealt.
Overwhelm - A unit or spell with Overwhelm will deal any excess damage to your opponent on your turn (does not work while blocking).
Quickdraw - Units with Quickdraw kill blockers before they can deal damage back. Note that Quickdraw only works while attacking, not while blocking.
Berserk - Units with Berserk can make a special double attack one time: If it survives the first round of battle, it will attack again. This can only be used once, and gives the unit Reckless.
Decay - When this deals damage to unit or relic weapon, that card’s strength and health (or armor) are permanently reduced by that much.