Protecting something... He can do that. The train appears to at least know some of his strengths, in that case. It's true that he's failed to protect some people in the past, but he'll still try his best here. Maybe he'll have the means to do better here.

As long as he doesn't accidentally hurt anyone he's trying to help.

"I hope that I can be useful to everyone." Wen Ning lowers his gaze to the ground. "Is everyone on the team... physically capable?" Are there those he'll have to look out for under his own color? They could have other skills that aren't made for fighting and that might not make sense for this team's purpose but he's sure there are reasons as to why they're organized the way they are.