Arc System Works has shared some new information on Double Dragon IV‘s story alongside the characters, modes and some features it’ll come with. Featuring the Double Dragon, Billy and Jimmy, here’s the story in Arc’s own words:
It is a continuation of the story in Double Dragon II: The Revenge, and features all new enemies! Defeat the on-rushing attackers, and try to clear all the stages!
The game can also be played with a friend!

(When first playing the game, Billy and Jimmy are the only selectable characters, but finishing all stages unlocks Tower Mode. Play this mode to unlock enemy characters for use in Story Mode.)
The game’s modes have been detailed as follows:
2P Duel Mode (two-player battle)
Progress in Story Mode to unlock extra characters for use in this mode! In this mode even enemy characters are selectable! They possess different skills to those seen in Story Mode, so try playing as all sorts of characters!
Tower mode (defeat enemies to advance upwards)
There are no continues! How far up the tower can you make it"

New playable characters useable in all modes will unlock depending on the number of enemies you manage to defeat.
Arc also teased that by playing the Tower mode, we might be able to unlock a “certain fan favorite character.”
Speaking of characters, here’s the confirmed list so far:

Billy
Jimmy
Williams
Roper
Right Arm
Linda
Abobo
Chin Taimei
Burnov
Linda (mohawk)
Mason
Cody
Yamazaki
Soeno
Ayumi

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