Well, now I know what I'm doing. Experience matters in this case, lol.
...though I may need to accrue all those curatives I wasted.
There is a way to fight him without using all your curatives. Get kitted up for GP - I usually bring 120 large mushrooms and 32 conquerors periapt for my assassin. Save as soon as you enter the chamber (if it didn't auto-save for you). Fight him, using all the consumables you want to. After the round is over, there will be an accessing server message, when it uploads the damage you did. After the accessing server message, godsbane and retry.
This method won't use up all your consumables. But beware, you won't be getting contribution credit on your game, since you didn't save the damage you did against Ur. So if you use this method, make sure you can get the kill during GP.
To the newer Ur fighters that didn't get a kill, try using periapts next time. Conquerors for strength based vocations, Demons for magic based. Bring 32 of your chosen variety. Four at a time will stack, so 32 should last you through the fight. Using the periapts is also a good way to gauge how much time you have left until Ur leaves, since each one (or set of four) will last for about a minute.
This method will boost your damage quite a bit - on the previous page someone already posted the link to Asgard's thread about periapts.
And it goes without saying that you should use all the strength and/or magic boosting augments that you have available.