You can’t disassemble your starter mount, but any other Rides you don’t like can be dismantled.
Usually, dismantling a mount, for example, a horse, you would assume there would be a fair amount of blood and organs, but in this case, it only gives you crafting materials to get another Ride you like more, which would give you quite a bad omen.
This Astellia Online patch will also add in a brand-new daily login reward tree, which is already here and will be there till January 26th, with players getting more rewards for frequent logins as well as a daily prize. Take a look at the full set of patch notes for more details on the patch notes and the balancing.