This can be for any au you want (Asgore as Undyne only), provided you give credit to original creator of the song. Please ask beforehand.
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Haven't listened to any Asgore BAaTH in a while so I took my own rendition of it.
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Leitmotives (In-order):
-Bergentruckung (Modified)
-ASGORE + Heartache
-Determination + Small Shock

Image by me

[Storyswap/Switched Up/An Asgore Battle Against a True Hero] The Mountain's Last HOPE

Hallo, I‘m an American communist who just wants to do whatever I can for my country. 

I’m an Undertale & Danganronpa fan & I love video game music & synth.

I’m sepiosexual & Agender, though you can call me whatever pronouns you like, I don’t care lol!

I’m still trying to figure out how to upload tracks on here even though I’ve used this site for a few years now. 
This segment will be deleted once I’ve posted my first track!

You still have no idea who I am... Ok some things about me, just a really busy 16 year-old guy who's spontaneously producing au tracks. I take requests ocassionally or when i have more free time. i work on many aus (including someone's au) and several UT fangames. I make roleswap au tracks a lot more than crossover ones. I mostly make death by glamours, battle against a true heroes, heartaches, and asgores because those are my favorites and really fun to make. I don't make megalos (really sorry but I'm just not really into that) though I make custom genocide run final bosses at some point.

And here's my discord: MoonStriker#0730

QnA:

Q: Do you have any AU?
A: Yeah, I have: Rolled Cycle (Swapspin), Last Hope, and Underswitched. "Will I make songs for one of theses aus?" Someday, yeah. 
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Q: Can I use your musics for my au?
A: Sure! If the description of the certain music says that, then yes! I'm wary about Deltarune aus, though.
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Q: Do you have any song project?
A: I consider "Chara and Asriel swap" to be my primary music project. There's more such as "Chaos Kings" and "Doused Flames". Upcoming project might be "Toriel and Asriel Swap" or "Mettaton and Asgore Swap". I'm not sure, but you can decide which one too based on what you're interested with.
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Q: Do you take request?
A: Yes, but that depends or it'll take some time to actually do it.
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Q: What is your favorite UT music?
A: For battle theme: Battle against a True Hero goes to number one! Death by Glamour goes to second! And finally... ASGORE goes to third! Last but not least... Heartache or Spear of Justice? I don't know, both are on-par to me =P As for area theme, Waterfall and Another Medium for the win!

[Storyswap/Switched Up/An Asgore Battle Against a True Hero] The Mountain's Last HOPE

MoonStriker (Archive II)