Im gonna say this deep from my heart it's the developers mistake how the game currently is when it's about selling and buying.
none of the developers said anything about any other item when they came back like undead hammer and other rare items but for helix as I said didn't show enough interest and that's not fair, might as well before giving the updates just tell us what items will be back and what won't be back and that's how it would become fair but instead we had no idea what's gonna return and what isnt and no a days out of no where we see not enough interest in bringing an item back, out of no where