The rogue will need some kinda of mobility ability like acrobatic leap to propel themselves over tanks. Wizards will need a short range teleport. Mobility abilities could really shake things up.
Well Collison detection imo is needed but combat is not a static event. Rogues can do leaps to get around people. Also tanks would need a knock back ability(on a timer). When someone is knocked back they would be thrown back regardless if players were behind them. Only environment collison detect would stop a knock back.
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The way mmo's were: Community, Exploration, Character Development, Conquest.
The way mmo's are now : Cut-Scenes,Cut-Scenes, solo Questing, Cut-Scenes...
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