Stix is a very strange sentient tool, with a... one of a kind personality. You will probably never get used to his strange antics.
He can, however, grow into a very valuable partner.
(Stix the Pick has a unique texture in the official Vox resource pack)
Sentient items level up as you use them, increasing their stats, enchantments, and attributes, starting at level 1 and maxing out at level 50.
They also whisper to you and have unique personalities. This is truly a one of a kind tool, special even among other sentient items.