I've been thinking what if I took that idea and made it better.
You can unlock things that do not affect the main game, but can be used in another mode that the game comes with.
I'm thinking of a card game with online play.
So by doing hard things in the main game, you unlock rare cards.
And the actual online card game will feature well animated 3D characters that would move according to your moves, which would look kinda like a turn based RPG.
Let me show you what the cards will look like:

Let's explain the rules of the game.
There are 3 kinds of cards, representing the 3 kinds of Demons that you see in the game. Robotic (blue), Mineral (Red), Particle (Yellow). You also get 1 deck for each kind, and each deck can have a max of 20 cards.
See the "A" at the top right of the card? That tells you the role of the demon, there are 2 roles, Attack (A) and Defend (D). Only Attack demons can attack, but to balance things out, if you cannot attack any of your enemies Attack Demons until they have 0 Defend demons in play.
Next, note under the name : "Ultra" this tells you the level of your demon. There are 6 levels:
Radio
Infra
Visa
Ultra
X
Gamma
In a normal play can work one of a few ways:
1) Play 1 Radio Demon.
2) Play 2 Radio Demons, but at least one of them must be face down.
3) Play 1 Infra Demon.
Radio demons are your grunts, and you are not penalized when they are destroyed. If you choose to play a Radio Face down, your enemy has the opportunity to take control of that Demon for 1 turn, that is unless you flip it face up before they call it.
Next notice the number "15" this is your demons Power of your demon, it also is their HP. When a demon takes damage, it is subtracted from it's own strength. When it reaches 0 your demon is destroyed.
Next off see the second, smaller, name "Combot." Kinda like pokemon, this tells you the demon you of lower-level which you need in order to play this card. The way this works is simple, if Combot is in your discard pile, than you can play Destrobot and move Combot to the bottom of your deck. This kind of play is called "Respawn."
Next see the 3 circles, P, R and C? Those indicate the possible ways that your demon can attack. Destrobot happens to be able to attack all 3 ways: Physical, Ranged, and Charge. Some demons will have effects that prevent them from being attacked a certain way, so this can really help balance things.
Another element that is not present in this card is "hexes" on the opposite side of PRC, some cards will have these hexagons. Each hexagonscan only be used once, and some demons can use them for different things, but all demons can use Hexes to dodge: If an enemy calls an attack on your demon, you can use one hex and be safe from harm.
Lastly, at the bottom is an effect. All demons have an effect. They may do very different things, and they may have different costs, some may drain your Power, some may take your hexes. But one thing that must be remembers is the terminology in the effect description:
D1 always refers to that demons self.
D2 refers to the single target demon. Any number greater than 1 refers to an enemy demon. Some demons can attack multiple demons, in which case the other demons will be refereed to accordingly:
Means that your demon can attack 2 demons in one turn.Attack D2 and D3.
You can have four demons in play at the same time. And up 6 cards in your hand.
At the start of your turn you pick a deck which you want to draw from, draw 2 cards, keep the one you like, and place the other at the bottom of the deck.
So here comes the master question. How do you win/lose?
A defeated demon will go to the discard pile. If a demon sits in the discard pile for more than 4 turns, it is removed from play. If you have more than 4 Demons removed from play that are of a level greater than Radio than you loose. You also lose if you have 8 Radio's removed from play.











