First semi-cheap suggestion to spring to mind is the "Black" runeword. Works just fine in flails.
Thul + Io + Nef. Only Io can be considered reasonably hard to obtain.
+120% Enhanced Damage
40% Chance Of Crushing Blow
+200 To Attack Rating
Adds 3-14 Cold Damage - Cold Duration 3 Seconds
+10 To Vitality
15% Increased Attack Speed
Knockback
Magic Damage Reduced By 2
Level 4 Corpse Explosion (12 Charges)
Two of thse give you a nice life boost and some cold damage to chill enemies. The damage isn't super, but hey.
Thul + Io + Nef. Only Io can be considered reasonably hard to obtain.
+120% Enhanced Damage
40% Chance Of Crushing Blow
+200 To Attack Rating
Adds 3-14 Cold Damage - Cold Duration 3 Seconds
+10 To Vitality
15% Increased Attack Speed
Knockback
Magic Damage Reduced By 2
Level 4 Corpse Explosion (12 Charges)
Two of thse give you a nice life boost and some cold damage to chill enemies. The damage isn't super, but hey.