Expansion parts provide the raw stat boosts required to survive level 100+ content. Do not waste slots on flat HP upgrades; focus on role-specific scaling. Primary Stat Focus Secondary Stat Focus Ideal Effect Melee Attack Boost Capacity Hate Up (Aggro generation) All-Rounder Balanced Attack Main Weapon Ammo Auto-Guard Sharpshooter Beam/Physical Ranged Role Action Speed Ammo Recovery on Crit Best Squad Composition for Solo Players