I've been working on this one for a while, and I'm happy I've finished it in time for the release of Dune 2!
The Ashworm Dragoon was a prestige class in DnD 3.5, meant as a "mundane" (as in, non-magical) special mount for fighters.
The two main hurdles when writing this class was finding a way to have the ashworm come back to the player in the event of death (most familiar subclasses in the game don't have this problem, as the character has spell slots to heal/resurrect their faithful friend) and balance the burrowing speed of the ashworm (I actually found that the rules are a bit more restrictive than I thought, and I've added a few more to prevent strategies that the players could employ to cheese encounters using their burrowing speed).
Yeah, I was trying to keep the subclass on the same level as the other fighter subclasses, but I can see how the later levels can feel a bit lame. I've added a few more things (+2 to the Sting saving throw at 15th level, and +1d6 to the ashworm's damage at 18th level), and I've reined back the Terror Cry ability (60 ft -> 30 ft, and it increases to 60 ft at 18th level).
As always, I'm very grateful for your analysis! I always try to imagine scenarios and run the math for my subclasses, but certain features always end up over/underperforming and it's difficult to see it without an external POV. I really appreciate your help.