Axe of the Heavens
Imbued
50% Hit Lightning
15% Hit Chance Increase
1% Defense Chance Increase
30% Swing Speed Increase
31% Damage Increase
Blade of Insanity
Imbued
100% Hit Stamina Leech
50% Hit Mana Leech
2 Stamina Regeneration
20% Swing Speed Increase
35% Damage Increase
Darkened Sky
Imbued
60% Hit Lightning
43% Hit Mana Leech
50% Hit Cold Area
10% Swing Speed Increase (60 stamina for 1.25s swings)
19% Damage Increase
Berserker's Maul
Imbued
40% Hit Mana Leech
60% Swing Speed Increase
12% Damage Increase
Wind's Edge
Imbued
50% Hit Mana Leech
50% Hit Stamina Leech
14% Defense Chance Increase
10% Swing Speed Increase (60 Stamina for 1.25s swings)
50% Damage Increase
I'll add more as I check them out...
Some are pretty cool upgrades, because they have non-normal stuff, like 100% Stamina Leech (Blade of Insanity). Others are just neat, but you could do the same thing from scratch (Like Wind's Edge). The advantage of getting an artifact is they have 255 durability to start from, saving you from using Powder. Or they have good hit types (50% Cold, 50% Energy for Darkened Sky).