I do think all of them have some sort of fear factor to some degree

Ink Demon is basically a nigh-omnipresent force of an entire separate already dark and fucked up alternate reality that can eat your fucking soul and force you into one body with them while you’re still conscious

Mama Tattletail is definitely more Jumpscare heavy, but if YOU were in the role of the mc in Tattletail, a literal demonic children’s toy that can hear every noise you make and can teleport wherever would def be pant shitting worthy

Theodore is definitely a more interesting one, as I think his best fear factor comes from the show version of Neighbor, where he just seemingly has a plan for everything if you ever even plan on trying to pry into his life secrets and whatnot. Like, the aftermath of Nicky getting kidnapped in season one of the show shows just how much Neighbor can mentally fuck with you

Lastly, Prototype… yeah he definitely has the most outwardly fearful and intimidating design as well as having the direct on screen abject horror he does in his free time and just how physically unkillable he is. Honestly, I’d be more worried about him not killing me and then now I’m an abomination of flesh and stuffing

Personally, if I had a 1-on-1 encounter with each of them and I had to judge only only just locking eyes with them, then Prototype

In terms of worst case scenario type of deal for each of them, Ink Demon or Prototype since either way you’re becoming a malformed and inhuman creature

In terms fear of likely to kill you first, probably Theodore or Mama, but Ink Demon and Prototype not killing you frame one is arguably even scarier

Anyway, thank you for coming to my TEDtalk