Okay, so there's a few different parts to this rec.

1. I want thrash metal that is a bit more slowed down or less brutal than Viking's Do Or Die with a better production

2. I need music that is fun, that helps create a party feeling. Any genre. Songs instead of just bands would be nice for this.

3. Bands/Albums/Songs that are trance inducing or that creates a soundscape. Doesn't have to neccesarily be metal.

4. Epic music for epic battles.

Thanks in advance!!

3. Tha-Norr...absolutely hypnotic
4. Warlord (US), Brocas Helm, Isen Torr, Solstice (UK), Atlantean Kodex, Thunder Rider...

Plan on fighting someone and need a soundtrack to go along with it?

No lol. Just being a nerd and wanting music for epic video games.

For number 4 try Bal Sagoth, or Equilibrium (Ger)'s first full length

2. Alestorm definitely.
And, Pantera's stuff like Cowboys From Hell (the song) which are really groovy should do the thing

better to ask these questions in the appropriate threads. e.g thrash metal help thread. you can ask for good party music in whichever rec thread you want it from. e.g heavy metal help thread, or thrash thread. just listen to municipal waste for party thrash

this band was amazing. Now to look into the rest of your recs...

3.) Nyktalgia, Astral Luminous
You might like those two bands. Both are fairly new, and play black metal. Astral Luminous also has ambience mixed in.

4.) Bal-Sagoth, Summoning
Bal-Sagoth, the most epic of epic bands. Absolute must, if you are looking for epic. Summoning is also great, possibly fits with the third category as well.

I'll name more if I think of any.