As long as the level of repair is persistent among all players then this is a great idea. I do not like they Hytbold model in that everyone get's their own personal Hytbold to repair. Areas of the wall could continuously be built up and damaged and the players efforts could have a real effect on the battle, similar to how fire oil in keeps works in PvMP.
Freeps: Venusia (Guardian), Silya (RK), Dwayr (Champion), Nissys (Captain), Filodon (Burgler), Tyveil (Lore-master)
Creeps: Venusiel (R7 Weaver), Tyveilakh (R5 Warleader)
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