making an undertale game

[Gors]

well my idea is adding mario and luigi to the game...

if you're doing gamedev like this then you should give up on this idea*

Click here to see why it's a bad idea, read this thoroughly.

You're completely approaching games as "fanfics" instead of games. You have brought literally nothing into the gameplay aspect. It's not your focus.

I know that there are many ways to create a game but ultimately you're going to PLAY it and if you don't bring anything new to PLAY the game then there's very little reason to actually make it. As I said, making a game is not "lol let's make a crossover fic plot with my 2 fave franchises out there" or "let's add nintendo characters even though nintendo likes to C&D shit"

This idea is basically very shitty and I suggest you to reconsider gamedev and embrace it as a more serious concept. Gamedev isn't about giving mario guns, or adding undertale to mario, or making Ana and Elsa's brain surgery minigames. Those are games - but other than the novelty factor of having a bizarre premise, they only add up to the sea of mediocre/bad indie games.

*unless if you don't plan on ever showing this game to anyone and use it for your own amusement instead. Yeah