Perk Rules

• Common, Uncommon, and Rare units have no perks
• Epic units have 1 perk slot
• Legendary units have 2 perk slots
• Mystic units have 3 perk slots

Rankup Cost

• Common to Uncommon: ~0 $WF and 2 Common Units
• Uncommon to Rare: ~0 $WF and 2 Uncommon Units
• Rare to Epic: ~0 $WF and 3 Rare Units
• Epic to Legendary: ~0 $WF and 4 Epic Units
• Legendary to Mystic: ~0 $WF and 4 Legendary Units