For me there’s a whole list of items that I consider “too valuable to throw away but not valuable enough to use”, in a lot of cases, which typically ends up with me piling them up for several lives, until I finally hit a NPC, convert them into generic items and feed them to a sentient weapon. So, out of interest, I’m compiling a little list here of items which can be stacked up pretty high in the inventory or bags; and turned into items that give sentient xp when you cash them in for it.

This is by no means a comprehensive list, and I’m always open to suggestions of new things to add or more efficient trade in options for collectables presented.

Collectable Most Efficient item Trade Collectables per sentient xp Notes
Mysterious Remnant Mysterious Cloak (lvl 21) 8000 rems = 105 sentient xp 76 rems = 1 sxp This can only be converted to sentient xp during rare events; appears to be once per 10 months or so
Thunderforge Ingot Tier 0 Weapons 20 ingots + 15 commendations = 110 sentient xp 1 ingot = 5.5 sxp This is a tradable currency; unlike most of the others on the list
Vistanii Totems Morninglord Weapons 60 totems = 290 sentient xp 1 totem = 4.8 sxp Farming these typically involves farming chests that drop ml29 named items, and are among the best for getting sentient xp in the game
Vistanii Talisman Barovian Weapons 40 talismans = 10 sentient xp 4 talismans = 1 sxp
Eveningstar Challenge Mats Min level 24 weapon 250 mats = 120 sentient XP 2-3 mats = 1 sentient xp Not all challenge mats are used in this recepe, and not all challenges give similar amounts of mats. In my experience; some challenges drop several hundred materials, while some seem to drop less then 30 mats in a similar length run. Other recepies are much lower mats/sentient xp turn ins.
Annaversary Party Favor Min level 30 items 100 favors = 300 sentient xp 1 favor = 3 sxp We've been informed that rose colored goggles; which used to be the best sentient xp/party favor is no longer availble. Party drops up to 8 favors per run (if you do higher difficulties). Unless I'm mistaken, the new best turn in is only 1/10 as efficient.
Shreds of Tapestry Muffled Veneer 20 tapestries = 11 sentient xp 2 tapestries = 1 sentient xp This is a tradable currency; unlike most of the others on the list. However it typically harder to get and less valuable then thunderforge ingots.
Codex Runes Tier 0 weapons 100 codex runes + 100 commendations = 130 sentient xp 1 rune = 1.3 sentient xp