Hey! I really love this and i wanted to make one just like this but a different sprite and sounds, is there anyway i could do this?
Hi! Sorry for taking a sec to reply, itch isn't notifying me about comments for some reason.
If you want to do it from scratch you could probably use something like python? This would be a lot easier than modding my app (see below.) The actual logic for the pet is pretty simple, it basically just queues an action and sets a random timer, then once the timer expires it executes the action, picks a new action based on the previous one and sets another random timer.
Personally, I molded gamemaker into being able to do this. If you have the knowhow you could probably use undertalemodtool to make a mod of it. Despite the name it does work for all Gamemaker games afaik. If not I've been wanting to publish the source code eventually, I just need to clean it up.
I'm not sure how well it would work but I did start working on adding support for multiple pet types so I could do over deltarune pets before I ran out of steam. You could define a new pet type based on Tenna and set the relevant var to your own pet, using the code from Tenna as a base/template. You can just replace Tenna's sprites and sounds directly, and this might be easier, but that still requires changing the animation definitions in the create event.
Anyway, I hope that made sense!! If you have any questions let me know and I'll try my best to help out.