Final Ludum Dare Game Project link: https://ldjam.com/events/ludum-dare/41/graveyard-dates

Some starting points:

1. You are the weapon: A game where you play as a living weapon – a spirit residing in a magical weapon who sacrificed herself in order to forge the sword, with abilities to shape-lift, evolve, develop enhanced speed and strength. Or a game where you carry a deadly virus / poison.
2. A light in the dark: A horror game with only one light source in the game, the ghosts are scared of it and that’s the only thing stopping them from getting to you. The player has to keep the light alive. Or a platform game set in a world of darkness and you have to chase the light.
3. Keep growing: An evolution game where you grow in size as you pick up items and progress through the level. You can’t reach certain parts if you are too small.
4. 3 rules: A story game set in a dystopian world where everyone has to obey 3 rules – wear a tracker, enforce a curfew every night and never question the leader, or a dungeon game where each level has 3 different rules.
5. Shelter: A stealth game where you have to find shelters and avoid being hit by sunlight.
6. Unusual magic: A game where you play as a magician with weird abilities to harness the power of words and will.e.g.everything you say comes true, the ability to feel the memories of antique objects and convert them into words, the ability to make your drawings crystallise into reality, etc.
7. Colour changes everything: a game set in a black-and-white world where everyone is miserable, the player have to progress through seven levels and defeat obstacles to restore colours to this world. Or a game world with a rainbow colour cycle system, when the colour changes all the elements changes(player, level, characters, enemies, music etc). 
8. At the beginning there is nothing: A horror escape game where you start with no resources and can only hide from your enemies, having to find your way out when everything is working against you. As you dig deeper, you accumulate resources and acquire powers to confront your enemies and progress the game.
9. Combine 2 incompatible genres (e.g. turn based racing): horror and romance –  a graveyard date simulator game with FPS elements / fighting dating game.
10. You really shouldn’t mix those: A magical substance mixing game where you play as a witch, there are many possible combinations with all sorts of dangerous results.e.g.turning yourself into a rabbit, creating new lives, getting yourself killed, psychedelic illusions etc.
11. Floating islands: A world building game inspired by the legends of Kuniumi, where you play as the god tasked with forming a series of floating islands to make up the world, or a survival game where you are stuck on a floating island.
12. It spreads: A world conquering game where you play as a character with a superpower to spread your emotions to affect other people, or a game to stop a hysteric laughter epidemic from spreading, or a genetics-oriented game where you organisms to spread.
13. The environment changes you: A game where you play as a character with chameleon physiology – your appearance and power changes according to the level. e.g. touching a material changes you.
14. Fragile: A metaphorical game where you have to protect your fragile memories from disappearing by catching them as they escape, or a story game / visual novel about fragile emotions and relationships.
15. You are what you eat: A cannibal superpower to turn into your enemy and absorb their power after you have eaten them.
16. Self-replication: A sci-fi game where you are an AI which learns to self-replicate and begin to take over the world, or an action thriller game where you have to find your clone who has been committing crimes using your identity.