Cross slash intro
The trailer begins with a city at night, the moon bright and yellow in the air, the sounds of chaos ringing in the air. The camera pans down to the hilltop overlooking the city, an armored figure looking down as the battle on the streets rages. The camera then zooms in towards the city and shows Cloud on his Fenrir bike, navigating through the streets as Ridley attempts to incinerate him with his Plasma Breath. Cloud deflects a few with the Buster Sword, and weaves around a few others, the fireballs melting half of passing cars and scorching buildings. Cloud jumps off and launches a Blade Beam at the Space Pirate, who whizzes past it and reaches to grab Cloud, only for him to smash the blunt side of the Buster Sword into the side of his head, causing him to careen to a building on the side. Cloud lands back on the Fenrir and looks back at the crash site before looking back forwards, only for him to crash into an Iron Block planted by Steve, who drops a lit block of TNT down towards his location. Cloud knocks the TNT back upwards and jumps upwards, only for Steve to Elytra-glide into Cloud's torso at full force, sending him careening into another nearby building. The former SOLDIER props himself back up on the Buster Sword as Steve and the now-recovered Ridley menacingly walk up to him. Cloud just barely makes it up and attempts to engage the two, only for the wall behind him to explode, a massive storm of wind causing chunks of rock to fly towards the Cunning God of Death and the World Crafter, who attempt to brave it only for them to be blasted into the wall behind them. Cloud looks behind himself and sees a blonde knight with a golden blade that soon seems to vanish, only leaving distortion to cloak it. The figure walks up next to Cloud as she looks towards Ridley and Steve, who seem to recover themselves and glare at her. She turns to Cloud.
"Can you still fight?"
Cloud lifts his Buster Sword, taking a bit more effort due to the Elytra-attack from earlier, but nods curtly.
"Then come. We shall fight them together!"
SABER Is Summoned To Battle!
The trailer then cuts to gameplay of Saber, the King of Knights, as she flourishes her currently-invisible sword. We then see her moveset, which heavily involves wind boxes and mana attacks. We then see her stage, Fuyuki City, which transports to multiple locations before showing a battle with Saber, Byleth, Ganondorf, and Link. We then see her Final Smash, her signature attack Excalibur, as she creates a massive golden blade above her before striking down with the force of a meteor, destroying everyone on-stage.
Super Smash Bros. Ultimate X Fate/stay night
We cap off with Ridley, sprawled on the floor, and multiple floating items indicating Steve didn't win either, as Saber and Cloud put away their respective weapons. Suddenly, Saber recoils in pain and falls to her knees. Cloud whirls towards her and kneels down, checking if she's okay as she grips her stomach.
"Z-Zounds...it seems I am faced with a new foe!"
Cloud looks around, his hand returning to the grip of his Buster Sword.
"No, it is not...one that can be seen..."
Cloud turns his attention back to Saber.
"It would seem...that now, hunger is the enemy!"
Cloud face-faults, all tension in the scene vanishing and giving way to humor. At that moment, Shirou Emiya arrives and sees Saber, who helps her up and brings her away back home for some cooking, leaving Cloud trying to recover from the drastic tonal shift.
@ 2018 Nintendo
Original Game: © Nintendo / HAL Laboratory, Inc.
Characters: © Nintendo / Hal Laboratory, Inc. / Pokémon. / Creatures Inc. / GAME FREAK inc. / SHIGESATO ITOI / APE inc. / INTELLIGENT SYSTEMS / Konami Digital Entertainment / SEGA / CAPCOM CO., LTD. / BANDAI NAMCO Entertainment Inc. / MONOLITHSOFT / CAPCOM USA., INC. / SQUARE ENIX CO., LTD. / ATLUS / Microsoft / SNK CORPORATION. / Mojang AB / TYPE-MOON