Well... he has something. Not rope, exactly. But he'd prefer not to use that option, if at all possible. He might very well try and kill Reiner like that. So holding on it is.

"Don't worry too much. I'm sure I can hold my balance."

And he shifts his weight over to the right. Holding on, as the giant version of Reiner moves.

"Do you think it headed back to the river?"