Just an idea..

I was just thinking maybe the game didn't really need much of a story since it was just a partial demo.. well it COULD have a story leading up to an event. My idea that just popped into my head was more or less about a battle instance or arena kind of thing where it's like smash TV you survive in there but the camera angle is 3rd Person view or like the view on God of War, Super Mario Galaxy, Sonic the Hedgehog Adventure (On Dreamcast), to have that kind of centered locked rotating camera on the character. The game play would be simply just destroying things over and over between rooms and rooms until you reach the boss level. Instead of collecting prize boxes like in smash TV for points, you collect orbs of experience or packets of energizers to replenish hp from damage taken during the battle in the enclosed room. Player characters will be choose able (so its not like levelling up you're choosing a preset character) each with their own special attribute/weakness/strength.

A neat function I had in mind was that each player could transform themselves into a different form for a temporary time after collecting bunch of orbs of experience or power ups of some sort and would be signified by a bar near their hp on whichever corner of the screen they are located with (4 players each player takes a corner to show their status). The competition is in the battle arena for whoever gets the most kills most stylish kills, most combo kills, most transformed kills, most team kills. Each room can have its own separate atmosphere such as like team killing, or ten-times damage monsters, boss battle, mini boss arena, bonus area, mega slowed down area. etc. (Multiple environments)

As for player development I didn't want a player to feel bored having the same character do nothing and over and over the same thing, I was hoping to rather they gain experience over the entire game, so to kill the repetition each player character can learn their own skill tree to help fight and make life easier rather then frustrating in game play but they should not be able to learn all of them and skills can be learnt only after a room is cleared when players can regenerate or plan their strategy for the upcoming level.

Controls for the game shouldn't be too complicated either, simply just directional keys or the WASD default for most FPS games except you're not looking through first person. space bar would be block/parry (Different characters could have a different way of defending, e.g. Agility hero would block by timing (Pressing it right when the attack is about to hit) not so much holding down the spacebar & eating every attack like a warrior, but would eventually break if taken too many) Attacking would simply be the mouse click left mouse, and right mous button would be to use skills and the middle mouse wheel is to scroll through your skills you've learned.

When players move from room to room it should be a majority or democratic vote, (portals on the direction to move towards ALL players must stand on that spot for all of them to move forward. NOT first person who gets there everyone moves with that first person)

anyways, feel free to burn, flame, criticize, commentate, give praise to, and add to this if any of you would like to.
EDIT: for a title i would just call this Battle Instance kinda simple and bland.. but... feels right.., for me anyways if it bugs you speak up!!

This is pretty cool, I like the simplicity of it.

The problem of repetition is not too bad so long as whats being repeated is fun and doesn't take a long time.
We could have something like randomly selected rooms to for people who like randomly generated stuff.

Have you ever played Thrill Kill?
In that when you attacked your enemy or got attacked your "Rage" bar filled, and once it was full you could unleash a super attack, something like that could work for the alternate shape aspect, or even as a stand alone attack aspect.

Maybe each room could have a different goal or something, first room you have to kill all the enemies, but the next one is all about item collection and so forth, that would give it some more variety, but the combat would be a constant element.

Ahh yes that's what I meant a rage bar kind of thing. I sort of came up with this idea after having missed the game Power Stone 2 on the dreamcast where you battle each other through cycling environments that are part of one stage entirely, and you collect stones and then you can transform yourself to do different attacks that deal more or cover more area for a limited amount of time. A super attack sounds great but the idea of 4 players doing that sounds quite overwhelming in one small room, maybe it can be enabled in certain rooms instead of transforming, or other rooms could just be puzzles instead of always combat, and the camera would just go overhead like bomberman view and people can just see what they have to do to complete the puzzles