I’ve noticed that the moonshaft rapier does frost damage and freezes opponents, despite having nothing in the description to indicate this and it’s base rune is Air Dodge.
I’m curious if there are more items like this. Personally, i love the idea of hidden bonuses that aren’t spelled out for the player.
Does it have a cold damage enchantment for chance?
It does not have the rune, but acts as though it does. One small observation is that it does not show the graphical ice effect if you’re not actively attacking (it will if you add the ice enchantment). While attackng, it displays the ice enchantment effect and will also freeze enemies.
no, i mean is it enchanted (blue/violet) and one of the perks is something like “add 3 cold dmg”
Nope. I’ve been using the base white versions. I’m pretty sure i tested this on one fresh out of the box, too. My current ones have gems (chipped spike, not ice dam). The next time i get a clean one I will retest.
in that case it sounds like a bug
I prefer to think of it as an “undocumented feature”. 
The Spirit Edge sword, that requires 42 Fait deals only cold damage on its base attacks as well as on its innate rune - Evasive Strike. It deals physical damage on infused runes or charged attacks (for some reason).
If enemies take enough cold damage they will get frozen ans stunned. Very strong weapon, borderline OP because everything that is not a boss is frozen in 1 hit.
Other “elemental” weapons I found so far are the staffs. Stag of Embers deals base heat; Cursed Krone base electric; Fallen Sky base cold & Spherin base plague.
Nice! That sounds a lot like a hidden quality. Thanks for sharing.