He definitely was going to leave the very important task of tracking the score up to the imperfect human memory. There's a pause where Strange mulls a few things over before deciding the battle isn't worth it, he'll go pick up a score card (though he knows he could accurately track the score himself, thank you very much.)

"I'll go grab a card and pencil—and don't steal any of my drink!" he says to the alien who doesn't need to eat or drink. The drink's Mountain Dew, Peridot probably wouldn't want it in the first place. And so, Strange heads back to the main hut to grab a scorecard and pencil.