Few suggestions:
1. double click should open the skill tree
2. If you have enough xp and gold, the game should automatically pick everything needed for a skill you click. Also undo
3. Skipping levels is a must
4. Inventory sorting
5. Not much of challenge right now
Interesting game with some potential.
Suggestion: Change view base and view map buttons to just one that toggles between them. Replace one of them with a button that goes through 3 different equipment sets: Farming, multi-target and single target.
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