That's the one thing you have going for you.

这是你唯一的优势了。

Now, the one thing you have going for you in your fight with Thanos is the fact his arrogance would be so high after beating everyone and fulfilling his objectives that you could not possibly be a threat to him.

现在，在与灭霸的战斗中，你要做的一件事是，在击败所有人并实现他的目标后，他的傲慢会如此之高，以至于你不可能对他构成威胁。