Apocalypse
Pacific Central Eastern 
London 
Istanbul 
India 
Jakarta 
Sydney Hero Progression Tool
Skill Book Calculator
Set the current and target level for each hero skill, then subtract the orange Skill Books already in your inventory to see exactly how many you still need.
Set your skill targets
1
Skill 1
Normal Attack Boost
Books required 0
2
Skill 2
Active Skill
Books required 0
3
Skill 3
Global Effect
Books required 0
Skill Book cost pattern
Each skill uses the same upgrade curve. A single skill requires 9,900 orange Skill Books to progress from level 1 to level 30.
Upgrade cost chart
| Target levels | Books per level | Range total |
|---|---|---|
| 2–5 | 100 | 400 |
| 6–10 | 200 | 1,000 |
| 11–15 | 300 | 1,500 |
| 16–20 | 400 | 2,000 |
| 21–30 | 500 | 5,000 |
| Level 1–30 | — | 9,900 |
The calculator follows the Skill Books progression shown in the requested LastZ Quick Calculators tool: three hero skills, levels 1–30, and the same cost curve for each skill.