I would like to propose some interesting ideas for the missing stages, there is the possibility that in the future we get?
A coastal village populated by frogmen, spaceships, futuristic machines take to the air in the background, strange electric shocks and experiments are seen in the distance, a very futuristic city!
During Ultra, spaceship attacking the city, is the time of superheroes!
(the background is taken from guild of wars 2).
It could be the secret of a castle, prison room,
where Mira holds human behind bars for their blood. hands of the detainees come from the bars during the match, desperate people who pray to escape.
Flocks of bats coming in from the windows at the top and go through the room.
screams are heard.
during Ultra, a cell opens and inmates escape, but are eaten by bats
( the background is taken from castlevania mirror of fate).
Omen bonus stage:
Sucked into the portal in the archives, we find ourselves in a new stage with the same characteristics of the flying platform stage from KI/2. You can always fall down from this stage, and you sucked from deep space into a black hole. The platform is a piece of a city in ruins, and orbits around flying city.
I think a Gothic bridge, in a place like Minas Morgul, the gargos castle could adapt well to the character, he has a hostile combat reminiscent of the creatures he creates resistance, then he will try to defend his castle creating a resistance to the deck .
During the battle, the castle glows green light, but becomes purple with large beams of light into the sky when it happens Ultra Combo, The castle opens the portals to other worlds.
a large and majestic temple, which brings together the atmospheres of the two historic sites of the first KI: the bridge over the lava, and the coliseum abandoned. A great temple built on the lava that collapses during the battle.
the arena is located at a road junction abandoned and full of war rubble during the battle a Raven falls on the way destroying everything and enveloping everything in the flames.