I collected data from multiple sources of drop rates, and listed all of them here. There was once a leaked file that showed the exact drop rates, but has been recently taken down by legal action from Deca.
0.026%
Hermit Jugg (per Tentacle Spawner)
0.05%
Quiver of Thunder (per Nature Sprite)
0.1%
Oreo
Conflict
Dirk of Cronus
Bulwark
Plague
0.2%
Ogmur
Sphinx Jugg
Between 0.2% and 0.3%
Resu 0.25%
0.5%
Tablet
1%
Candy Coated
Cutlass
Ancient Stone Sword
Leaf Bow
LoD Armors
Skull of Torment
Puri
Doom Bow
Demon Blade
Shatters Rings
1.5%
Firecracker Katana
Ray Katana
Crystal Wand
Harlequin
Dancing Swords
Fulmi
Spirit Dagger
Arachna Doku
2%
Thessal Coral Bow
Esben UTs
Illumination
Morning Star
Ghostly Prism
Lab Robe
Prot
Conduct
BftN Vanities
3%
Planewalker
EP
5%
Coral Gift Ctrap
8%
Thessal Coral Trap
Crystal Sword
Tomb Rings
Chicken UTs
10%
Coral Gift Cbow
EDIT: added jugg drop rate per tentacle spawner
This is all of the exact data I received, but I’ll edit them if there are some changes to be needed.