There's a VVVVVV motif in Cool Mixtape and Attack of the Killer Queen plus the Queen Motif (the first one introduced) sounds very similar to the background melody of Pushing Onwards from VVVVVV.
What's VVVVVV and what does it have to do with Deltarune
It's a videogame with music composed by Magnus "Souleye" Palsson. I think Toby Fox took inspiration. Also the flavor text for Kawkaw's R-action is a reference to VVVVVVV. "Ralsei offers shiny trinkets" like how in VVVVVVV when you collect an optionable collectable, flavor text appears on-screen saying "You got a shiny trinket"
Ok, but even if Toby did take inspiration from the game or use a motif, why would that be listed on this wiki?
I'll go get @Vexodus
HE'S AWAY
oh.
I forgot about that but if there's anything about leitmotifs that I don't know, I think Vexodus would be able to help.
Toby Fox used leitmotifs from other songs so why not include that he borrowed a leitmotif from another game that I like.
TO: a really good video game
VVVVVV? 
TO: yes
@Tomeh I am a fan of your remixes of deltarune songs.
TO: thank you :D
what part of pushing onwards exactly?
2:25 
thats the wrong question. the correct one is "why would toby fox take a leitmotif from something he didnt work on at all".
and to answer that question, because that's how wikis work.
this sounds nothing like queens theme
It's the melody of the song. Also the melody first appears in Deltarune as Cool Mixtape. Try listening to them and compare them. 
yeah i cant hear it at all