I was stacking bleed on the undead 1 skull skeleton boss with the spear in the War Maker’s dungeon. Pretty certain this isn’t supposed to happen. I don’t know whether the bleed stacking glitch applies to the other bosses in the dungeon as I didn’t try it. I suspect bleed will stack on them too though.
Which boss are you referring to? One of the tall guys who drop the statues for the puzzle? They seem to be susceptible to both Bleed and Poison (on the live game too, not just Testlive), so I’m not sure if they’re actually undead per se. Feels like an intended feature. The actual undead folks down there, including the glowy blue bosses, seem to be immune to Bleed and Poison.