Npcs schedules. It's worldbuilding and open world

The solar sensor in the cartridge that actually wants real sunlight. Making it a base mechanic

The strand system, actually helping each other. making delivery idea for a AAA game

Talking to virtual girls. Real time dating

Combining devil May cry and resident evil

If you have a music cd you can actually play these in game and game will make custom level for it

Entire base rolling system

The meat timer

Soul system / phantom mechanic. Making soulslike subgenre

Holding hands... and being able to protect someone

Cinematic espionage action

Hack n slash mecha

The story itself and some ending changers

Hovering around and world building

Combining rpg elements and metroid like gameplay. Making metroidvania genre

Rpg elements into racing with some cool story too

Hack n slash formula

Espionage and stealth mechanics

A side by side gameplay. Absorbing bullets

Outrun formula with tricks

Using ds's features for it's puzzles

Changing platforms with Perspective

Gigolo mode

Using vita's camera and making some photos appear ingame

A perfect 2d to 3d transition of difficulty

First person shooter with rhythm

The judge system

Using vocals in it's music and very difficult drift system

Effecting other gameplay scenarios and it's impossible n64 port

Creating tactics subgenre

Being able to Parry everything. Making it harder to master

Being able to change every move. Making it the best 3d beatemup

Virtual pet mechanics

Comic book style storytelling