A small arrow or indicator above the enemy that your ranged attack or skill will target. Turns red when out of range (toggleable)
Rogue's aimed shot, mage's fireball, warrior's axe throw etc.
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Better boss HP bar.
Instead of a basic green HP bar. Make it detailed, stylized & unique to each boss. & also display various buffs/debuffs inflicted on the boss next to the HP bar.
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