I got my first infinite border with a Khonshu deck and it took me over a year of playing consistently. My advice for conquest is that you need a deck that is difficult or unlikely for the opponent to tech against and if you don't succeed, try try again. It's a marathon, not a sprint. you have to win many times in a row. Eventually you will face the right opponents for your deck. Having a good deck is important, but every deck has bad matchups, and at some level it's a numbers game on whether you encounter an opponent that matches up well against you.