You’d think that a film studio with limitless amounts of money at its disposal would be incapable of making spelling errors, but you’d be wrong. We’ve seen it time and time again where movies misspell simple words, which only causes the audience to laugh at the typo in theaters. To Iron Man’s credit, this typo only appeared on screen for a brief moment, so nobody in theaters could’ve pointed it out.
Nobody “takes reigns” over something. They meant to say “take reins,” as in the reins of a horse. “Reign” means to rule over something like a king or general would.