The Ninth Night [Written, Filtered to Sonic the Hedgehog, 100%]

[After some of the initial planning for the attack has been made, Batman found himself in possession of a certain sword.  Now, to make good on his ability of getting it back to the Samurai when he needed it most.  And there was one person he knew he could turn to that was heading to the front lines.  Plus... he could prove helpful in getting Batman some of his much needed equipment when the time comes.]

Sonic,

Meet me outside Community Building Seven in two hours.  There is a matter I wish to discuss concerning the Blue Rogues.

[The message is signed with a drawn version of the bat symbol.  Of course, the end part is a lie.  But if the Rogue Malnosso are observing him, he needs to make this look good.  He's hoping Sonic can figure out that he's putting on a show.]