Your exploring an Arkham Institution with the Suicide squad in Metropolis (Harley Quinn,Captain Boomerang,king shark,deadshot)

Captain boomerang grabs flash and pins him against a wall,then accidentally cuts his finger off... A guard screaming for help before he gets swooped away in a sudden blur of movement....The guard gets thrown onto the floor,his neck snapped, another guard comes stumbling in with a batarang impaled through his neck before he falls onto the floor

Batman then jumps down "There you are..." he says in a sister tone as his eyes glow purple

he grabs his disrupter and shuts off all your team's weapons before disappearing....explosive gel can be found near some doorways