Final Battle Team-Up
From SmashWiki, the Super Smash Bros. wiki
Final Battle Team-Up is a co-op event match in Super Smash Bros. for Wii U. Both players must choose a character and take on playable antagonists as well as Link and Samus in their dark alternate costumes, and Meta Knight in his navy alternate costume.
This event is unlocked by clearing An Offering of Coins. Completing the event on its own does not unlock any further paths. However, after both the event is completed and all characters are unlocked, the down path is revealed.
Completing the event on hard difficulty awards 5000G.