Interesting concept ! You really implemented well the choice of using worms as your faction, everything is flavorful. As some have mentioned, there are still references to the previous board with "Den", "Psychosis" or "Parliament", but otherwise the transition from owls is really clean. I do have some questions about the Tremor tokens.
What is the use of tremor slots ? they don't seem to be doing anything mechanically, and most often opponents return them to your suply, did I miss something ?
Do tremors need to be tokens at all ? They never go on the board, but or only given to other players, couldn't they be markers ? Or otherwise they could be cards with " Once per turn, you may give to the Annelid's player a card matching a clearing with Annelid warriors and your pieces to return this card to their supply". It could free up some space on the board.
Overall great twist on a "secret piece" faction, well done :)