Skill Boosters

You learn **Skill Boosters** from the Skill Books that appear when you clear stages by fighting. You continue learning new skills as you clear further Skill Book stages in the dungeon. Once you've acquired and activated the booster, using it enough times will upgrade it to a stronger version. (For example, after you have used Bloodrage five times in the same dungeon, you will automatically acquire the more powerful Bloodrage **+**.)

Having the right combinations of skill boosters can form a Booster Synergy, an advanced skill boost more powerful than any one skill booster alone.

As long as you don't start a new dungeon, you will continue stacking new skills on top of your old skills by finding more books. When you start a new dungeon (or restart the current one), all skill boosters are lost – you start each dungeon with no boosters at all. Leaving the dungeon to go to your castle only removes skills learned since the last checkpoint stage.

**MISSING:** Add icon images (they're already uploaded to wiki)

### Booster List

*This list includes booster synergies – special boosters that you won't find in the Skill Book. A synergy is formed by combining compatible skill boosters once both the skills have upgraded.*

*More details for the synergies can be found on the synergies page.*

###### Ambush

After a Dash, increase your Team's movement and attack speed for 25s.

Upgrade requirement: 15 uses

###### Ambush **+**

After a Dash, increase your Team's movement and attack speed for 4s.

###### ATK UP

Increases Summon ATK by 40%. Upgradable after hitting the target with cast skills multiple times.

Upgrade requirement: 30 uses

###### **Black Mist Trail**

Leave a powerful dark mist when you move. The mist can deal damage and apply Poison effect to the enemies.

You automatically acquire this synergy when you have both Poison Trail **+** and ATK UP **+**

###### Bladestorm

Call down a bladestorm when you deal critical damage.

Upgrade requirement: 12 uses

###### Bladestorm **+**

Call down a powerful bladestorm when you deal critical damage.

###### **Blade Master**

Call down a powerful bladestorm when you deal critical damage. The Team releases a circling sword as one step in the bladestorm.

You automatically acquire this synergy when you have both Bladestorm **+** and Swift Summon **+**

###### Bloodrage

As you get injured, the whole Team ATK increases gradually.

Upgrade requirement: 5 uses

###### Bloodrage **+**

As you get injured, the whole Team ATK increases gradually and quickly.

###### Chain Lightning

Grant a chance on attack to release a bolt of lightning that leaps between at most 3 targets.

Upgrade requirement: 36 uses

###### Chain Lightning **+**

Grant a chance on attack to release a bolt of lightning that leaps between at most 4 targets.

###### Combo

Small chance of dealing additional damage.

Upgrade requirement: 36 uses

###### Combo **+**

Medium chance of dealing additional damage.

###### Crit. Rate UP

Increase Summon Crit. Rate by 20%. Upgradeable when Summons make enough Crit. attacks.

Upgrade requirement: 30 uses

###### **Deadly Poison**

***needs description***

You automatically acquire this synergy when you have Poison Strike **+** while Reichenbach is in your team.

###### Flame Blast

When you get injured, call down a giant meteor to attack nearby enemies. 6s Cooldown

Upgrade requirement: 3 uses

###### Flame Blast **+**

When you get injured, call down a larger meteor to attack nearby enemies. 5s Cooldown

###### Flame Orb

Summon 2 Flame Orbs hovering around you and can crash into enemies.

Upgrade requirement: 30 uses

###### Flame Orb **+**

Summon 4 Flame Orbs hovering around you and can crash into enemies. The Orbs move faster than with the lower version of the skill.

###### Flame Spirit

Summon up to 2 Flame Spirits that can bounce once on obstacles.

Upgrade requirement: 20 uses

###### Flame Spirit **+**

Summon up to 3 Flame Spirits that can bounce once on obstacles. The Spirits move more quickly than with the lower version of the skill.

###### **Flamebringer**

***needs description***

You automatically acquire this synergy when you have both Flame Orb **+** and Flame Spirit **+**

###### **Growing Poison**

***needs description***

You automatically acquire this synergy when you have both Poison Spirit **+** and Strong Will **+**

###### Ice Blast

Stack 1 instance of Ice effect on nearby enemies when you are injured.

Upgrade requirement: 3 uses

###### Ice Blast **+**

Stack 2 instances of Ice effect on nearby enemies when you are injured.

###### **Ice Shield**

***needs description***

You automatically acquire this synergy when you have both Ice Blast **+** and Invincible **+**

###### Ice Crystal

Critical attacks have chances to generate upgradable Ice Crystals (up to lvl 3).

Upgrade requirement: 10 uses

###### Ice Crystal **+**

Critical attacks have chances to generate upgradable Ice Crystals (up to lvl 4).

###### **Icey Armor**

***needs description***

You automatically acquire this synergy when you have both Ice Crystal **+** and Shield **+**

###### Ice Strike

Stack 1 instance of Ice effect upon each attack.

Upgrade requirement: 200 uses

###### Ice Strike **+**

Stack 2 instances of Ice effect upon each attack.

###### **Icey Wisdom**

***needs description***

You automatically acquire this synergy when you have both Ice Strike **+** and Super Serum **+**

###### Invincible

As you get injured, grant you invulnerability and increase 100% movement speed for 2s.

Upgrade requirement: 3 uses

###### Invincible **+**

As you get injured, grants you invulnerability and increases movement speed by 100% for 3s.

###### **Lightning Area**

***needs description***

You automatically acquire this booster synergy when you have both Lightning Vortex **+** and Unsheathed **+**

###### **Lightning Storm**

*needs description*

You automatically acquire this booster synergy when you have both Chain Lightning **+** and Crit. Rate UP **+**

###### Lightning Vortex

Summon a remaining Lightning area after Dash.

Upgrade requirement: 15 uses

###### Lightning Vortex **+**

Summon a larger remaining Lightning area after Dash.

###### **Meteor Impact**

***needs description***

You automatically acquire this booster synergy when you have both Flame Blast **+** and Ambush **+**

###### **Missile Sword**

***needs description***

You automatically acquire this booster synergy when you have Tracking Sword **+** while Zorron is in your team.

###### **Mjolnir's Wrath**

***needs description***

You automatically acquire this booster synergy when you have Thunder Fall **+** while Thor is in your team.

###### Poison Spirit

Summon explosive Poison Spirits (up to 2).

Upgrade requirement: 20 uses

###### Poison Spirit+

Summon bigger explosive Poison Spirits (up to 3).

###### Poison Strike

Stack 1 instance of Poison effect upon each attack.

Upgrade requirement: 200 uses

###### Poison Strike **+**

Stack 2 instances of Poison effect upon each attack.

###### Poison Trail

Leave a poisonous mist when you move. The mist can apply Poison effect to the enemies.

Upgrade requirement: 200 uses

###### Poison Trail **+**

Leave more poisonous mists when you move. The mist can apply Poison effect to the enemies.

###### **Rampage Combo**

***needs description***

You automatically acquire this booster synergy when you have both Combo **+** and Bloodrage **+**

###### Shield

Grant a shield every 30 seconds.

Upgrade requirement: 3 uses

###### Strong Will

Gain 10% lifesteal when your HP is below 25%.

Upgrade requirement: 30

###### Strong Will **+**

Gain 10% lifesteal when your HP is below 40%.

###### Super Serum

Increase Summon HP limit by 40%. Upgradeable when you cast enough amount of Summon skills.

Upgrade requirement: 10 uses

###### Swift Summon

Each Summon's hit reduces the remaining cooldown of all Summon skills by 0.3s.

Upgrade requirement: 50 uses

###### Swift Summon **+**

Each Summon's hit reduces the remaining cooldown of all Summon skills by 0.6s.

###### Thunder Fall

Unleash a powerful lightning strike in an area, damaging enemies every 3s.

Upgrade requirement: 10 uses

###### Thunder Fall **+**

Unleash a powerful lightning strike in an area, damaging enemies every 1.5s.

###### Tracking Sword

Call down a flurry of swords that target enemies.

Upgrade requirement: 60 uses

###### Tracking Sword **+**

Call down a flurry of swords that target enemies, fly through enemies and bounce.

###### Unsheathed

Grant bonus damage on the first attack to full HP enemies.

Upgrade requirement: 20 uses

###### Unsheathed **+**

Grant bonus damage on the first attack to full HP enemies.

##### New with version 1.2.0 (incomplete)

###### Resurrection of the Dead

Summon a Skeleton Soldier when an enemy dies nearby, with a 10s cooldown.

Upgrade requirement: 15 uses

###### Resurrection of the Dead **+**

Summon a Skeleton Soldier when an enemy dies nearby, with a 5s cooldown.

###### **Death's Frenzy**

***needs description***

You automatically acquire this booster synergy when you have Resurrection of the Dead **+** while Nefara is in your team.

###### Death's Reward

Recover 2% of HP when an enemy dies.

Upgrade requirement: 15 uses

###### Weak Aura

Reduce the ATK of enemies within a small range nearby.

Upgrade requirement: 30 uses

###### Weak Aura **+**

Reduce the ATK of enemies within a larger range nearby.

###### **Vampire Aura**

***needs description***

You automatically acquire this booster synergy when you have both Weak Aura **+** and Death's Reward **+**.