The majority of my tries have been failures, with some going 13-14 minutes or 1-2 minutes off my line. Only a couple have been 12 minutes, and i have felt so frustrated when i missed the hermes would be jealous in just above 1 second(12:01 with Achilles Spear, Sea Storm Combo) I have tried demeter fists(merciful end) hestia rail , beowulf and pretty much all the weapons i can think of. Why is getting a time under 12 minutes. Do you have any advice?

Even just reaching the 12 minute mark can be difficult for casual players, and even learning a bit of speedrunning information is massively helpful to breaking ~10m barriers. Highly recommend joining the Discord (linked icon under the Follow button), people will gladly offer advice and can even do video reviews, and generally it holds a ton of useful knowledge.

You could always post a video of one your runs. Would make it easier to spot things that could be improved. The only weapon I know how to play decently is Fist Merciful End combo, but I'm sure other people could help you with other weapons. Other than that have fun, try to improve slowly and know that the majority of everyone's speedrun attempts are failure due to the luck factor in this game.

in my opinion, heris canon (especially with roquet launcher + five bombs) is the easiest way to do a good time.

i play it with at least Zeus (atack, static discharge) and poseidon (tech, dash, razor shoals) + sea storm. You need privileged status in the miror.
For the pact: forced overtime max and extreme mesure 2.

In your run you should take the quickest way (chaos, charon, patrocle,...)

hope it help you.

I'm just starting out, but for under 12 minutes I've found the Talos fists great. Dump loads of power from whomever you find first into the special, spend your run basically buffing your special as much as possible and going for duo combos as the opportunity arises. I just submitted my first sub 11 time with a Zeus special and Jolted as my two main boons, and Quake Cutter as the first hammer upgrade. So not a particularly special build really. I also had Poseidon's tidal dash and Artemis's pressure points for random critical hits.

Talos is great because instead of charging around the map looking for the enemies you can pull them in using the magnetic special.