Version

Knockout Blow

RegentAttackUncommon
Deal 30 damage.
If this kills an enemy, gain .

A 30-damage hit, 38 upgraded. If the target dies from it you gain 5 Stars at once. The code checks the damage result rather than the Fatal keyword, so a minion kill pays out too. The Stars arrive as a gain, which triggers Black Hole and counts for Radiate that turn.

Character
Type
Attack
Rarity
Uncommon
Cost
3 Energy
Target
One enemy

When to take Knockout Blow

A finisher for group fights in Act 2, where a kill refunds Stars for Comet or Seven Stars. Three Energy is heavy, so skip it without Star sinks, and upgrade it for reliable kills.

Cards that synergize with Knockout Blow

Comet
Attack
0
5
Deal 33 damage.
Apply 3 Weak.
Apply 3 Vulnerable.
Comet and Seven Stars spend the five Stars.Deal 33 damage.
Apply 3 Weak.
Apply 3 Vulnerable.
Seven Stars
Attack
2
7
Deal 7 damage to ALL enemies 7 times.
Comet and Seven Stars spend the five Stars.Deal 7 damage to ALL enemies 7 times.
Radiate
Attack
0
Deal 3 damage to ALL enemies for each gained this turn.
Radiate deals 3 per Star gained this turn, so 15 to all.Deal 3 damage to ALL enemies for each gained this turn.
Black Hole
Power
1
Whenever you spend or gain , deal 3 damage to ALL enemies.
Black Hole fires on the gain.Whenever you spend or gain , deal 3 damage to ALL enemies.
Know Thy Place
Skill
0
Apply 1 Weak.
Apply 1 Vulnerable.
Exhaust.
Know Thy Place adds Vulnerable to secure the kill.Apply 1 Weak.
Apply 1 Vulnerable.
Exhaust.
Child of the Stars
Power
1
Whenever you spend , gain 2 Block for each spent.
Child of the Stars turns the Stars into Block.Whenever you spend , gain 2 Block for each spent.
Decisions, Decisions
Skill
0
6
Draw 3 cards.
Choose a Skill in your Hand and play it 3 times.
Exhaust.
Decisions, Decisions costs Stars, and Knockout Blow gains themDraw 3 cards.
Choose a Skill in your Hand and play it 3 times.
Exhaust.
Neutron Aegis
Power
1
5
Gain 8 Plating.
Neutron Aegis costs Stars, and Knockout Blow gains themGain 8 Plating.
Royal Gamble
Skill
0
5
Gain 9 .
Exhaust.
Royal Gamble costs Stars, and Knockout Blow gains themGain 9 .
Exhaust.
Devastate
Attack
1
4
Deal 30 damage.
Devastate costs Stars, and Knockout Blow gains themDeal 30 damage.
The Smith
Skill
1
4
Forge 30.
The Smith costs Stars, and Knockout Blow gains themForge 30.
Alignment
Skill
0
3
Gain .
Alignment costs Stars, and Knockout Blow gains themGain .
Astral Pulse
Attack
0
3
Deal 6 damage to ALL enemies twice.
Astral Pulse costs Stars, and Knockout Blow gains themDeal 6 damage to ALL enemies twice.
Dying Star
Attack
1
3
Ethereal.
Deal 9 damage to ALL enemies. ALL enemies lose 9 Strength this turn.
Dying Star costs Stars, and Knockout Blow gains themEthereal.
Deal 9 damage to ALL enemies. ALL enemies lose 9 Strength this turn.
Gamma Blast
Attack
0
3
Deal 13 damage.
Apply 2 Weak.
Apply 2 Vulnerable.
Gamma Blast costs Stars, and Knockout Blow gains themDeal 13 damage.
Apply 2 Weak.
Apply 2 Vulnerable.
Reflect
Skill
1
3
Gain 15 Block.
Blocked attack damage is reflected to your attacker this turn.
Reflect costs Stars, and Knockout Blow gains themGain 15 Block.
Blocked attack damage is reflected to your attacker this turn.
Resonance
Skill
1
3
Gain 1 Strength. ALL enemies lose 1 Strength.
Resonance costs Stars, and Knockout Blow gains themGain 1 Strength. ALL enemies lose 1 Strength.
The Sealed Throne
Power
1
3
Whenever you play a card, gain .
The Sealed Throne costs Stars, and Knockout Blow gains themWhenever you play a card, gain .
Falling Star
Attack
0
2
Deal 8 damage.
Apply 1 Weak.
Apply 1 Vulnerable.
Falling Star costs Stars, and Knockout Blow gains themDeal 8 damage.
Apply 1 Weak.
Apply 1 Vulnerable.
Guiding Star
Attack
1
2
Deal 12 damage.
Draw 2 cards.
Guiding Star costs Stars, and Knockout Blow gains themDeal 12 damage.
Draw 2 cards.
Meteor Shower
Attack
0
2
Deal 14 damage to ALL enemies.
Apply 2 Weak and Vulnerable to ALL enemies.
Meteor Shower costs Stars, and Knockout Blow gains themDeal 14 damage to ALL enemies.
Apply 2 Weak and Vulnerable to ALL enemies.
Particle Wall
Skill
0
2
Gain 9 Block.
Return this card to your Hand.
Particle Wall costs Stars, and Knockout Blow gains themGain 9 Block.
Return this card to your Hand.
Quasar
Skill
0
2
Choose 1 of 3 random Colorless cards to add into your Hand.
Quasar costs Stars, and Knockout Blow gains themChoose 1 of 3 random Colorless cards to add into your Hand.
Cloak of Stars
Skill
0
1
Gain 7 Block.
Cloak of Stars costs Stars, and Knockout Blow gains themGain 7 Block.

Relics that synergize with Knockout Blow

Intimidating Helmet
Intimidating Helmet triggers on cards that cost 2 or more, and Knockout Blow is oneWhenever you play a card that costs or more, gain 4 Block.

Changes by version

  1. 4 Sep 2025ArtInternal playtest
    Added portrait art
  2. 16 Jan 2025Bug fixInternal playtest
    Knockout Blow card now properly triggers after killing a Decimillipede Segment
  3. 1 Nov 2024RarityRareUncommonInternal playtest
    Rarity changed from Rare to Uncommon
    Upgraded damage3538Internal playtest
    Upgraded damage increased from 35 to 38
All 6 patch notes3 older
  1. 23 Aug 2024RarityUncommonRareDamage26(31)30(35)Star4(5)5Internal playtest
    Rarity changed from Uncommon to Rare, Damage increased from 26 to 30 (upgraded 31 to 35) and star gain changed from 4 (5) to 5
  2. 29 Jun 2024TextInternal playtest
    Replaced number in Knockout Blow with multiple star icons
  3. 7 Jun 2024AddedInternal playtest
    Added Knockout Blow card

Internal playtest notes are from before the Early Access release. Names and numbers in them can differ from the game today.

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