From the ShadowsG 10

Finish arcade mode with each Hidden character (Marvel vs. Capcom)

Please sign up or login to post guides or tips for this achievement.

We don't have any guides for this achievement yet

Keypress	Action
`s`	Move focus to site search box
`r`	Move focus to quick reply box in a thread or message
`n`	View the first unread post in a thread
`f`	Toggle and scroll to filter options (on select pages)
`?`	Toggle keyboard shortcut help dialog