for starters i guess you could compare this new boss/raid boss to raid1 and diablo together? but harder
what would it drop i talked about it in my other topic about new magic armor? new magic armor that has prayer restore on hit and % drop rate +staff with more bonus prayer restore to help with lots of prayer draining bosses such as magegray chaos ele raid bosses
what it could look like it could be a old holy warlock as the robes would most likely be holy based that or some sort of a bright white spider that drops silk to build the new armor/weapon?
how would it attack i'd suggest two attack style's if going for holy warlock melee/mage if spider melee/ranged
restrictions i dont think it should have any
a special attack for the warlock it could heal itself everyone couple seconds or minutes depends how hard you make the boss with hp and defence as for the spider it could have a special attack that brings all players close to it for a strong melee attack and poisons them
Sorry if you dont make much sense since im not that good at typing sentence :PPPPPPPP