Uh, asking that is like asking how can you beat magic, or gravity, because apparently in that verse, Determination is one of the fundamental force of that universe (just like Flash-verse have Speed Force), or so it seem (such great amount of power would theoratically create a world run purely on GAR, like Gurann Lagant. That world would be impossible to hide from the blatant effect it would show on the universe. Or even more simpler, the human society (of that world) would have discover it a long time ago and have exploited it to death( or eternity, as it effect would said). But that just pure speculation on my part)
Specifically though, you need to specified what kind of "beat" you want. If it just beating it out of the opponent, you could just isolate them from the rule of that force, like putting them in another dimension or have them reject it itself, or you could have an illusion to have beat it by overpowering it with some other force, making it inconsequential. (Just like pure determination alone couldn't beat gravity in our world). If you want to beat the effect of it, either doing like the above to yourself, or become one with it . IF you want to defeat the thing itself in physical form, like said you want to destroy the law of a country, you only need to beat down the system that support it, like a goverment, a mystical crystal that magic is based on, or part of the universe, or again, creating a special zone that's not allowing it to work.AND IF you want to defeat it as a concept, then that is a job only high-lever reality warper can do.
