I have seen triple immunity before; not quadruple. I dont see why it shouldnt be possible to be created, it is just so very unlikely.

This is an artifact of the randart code, which uses one number rather than 2 to compute power. Normal artifacts have positive powers and (sometimes) negative powers. If you add them together for cursed artifacts, you end up with something weakly negative with no redeeming value.

Not a randart, but a big step up from Dagmor for my cl 30 mage:

the Lochaber Axe 'Redhele' (11d8) (+12,+11)
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Slays dragons (powerfully), undead.
Branded with weak fire.
Provides resistance to fire, cold, poison.
Cannot be harmed by acid, fire.

for those times when you need those dragons really, really dead.

this is why randarts is life:

the Multi-Hued Dragon Scale Mail of Erelch (-2) [45,+22] <+14>
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+14 speed.
Provides resistance to acid, lightning, fire, cold, poison.

Daaaaaang. What kind of damage does that do? Lochaber Axes are one of my favorite weapons in the game.

i gonna guess something in the 1200/1300 range.

a) the Short Sword of Arethil (8d7) (+17,+12) [+10] <+2>
Found lying on the floor in a vault at 3300 feet (level 66)

+2 attack speed.
Slays evil creatures.
Cannot be harmed by acid.

Combat info:
8.0 blows/round.
Average damage/round: 1082.4 vs. evil creatures, and 796 vs.
others.

i also had a shield of Lightning brand that brought the damage vs electicity to 1300.

Thats a winner. It has the 3 best modifiers - dice, blows, slay evil.

You can definitely take that Dracolich. And that Sky dragon.