If you have read my article about restricting the scope of your first game, you might want to give it a try, but it can be quite tricky to come up with an idea that would be small enough to finish quickly. I remember it took me quite some time to find inspiration for a game of small enough scope to finish in a short time frame.
Here you will hopefully find some inspiration. Just remember, skip the online multiplayer and avoid 3D. Your AI if you need one, shouldn't try to think like a person, just make some if statements. Don’t bother much with design patterns unless you want to give one a try before going for a bigger project. Ask yourself if there is a chance to finish this project in 2 - 4 weeks granted the knowledge that you already have. If you think it might take longer, try to cut off features for now until you have a shorter list of things you don’t know about yet.
If you don’t know what language or engine to use, pick what you are already familiar with. If you are just starting your journey, I think the easiest and least overwhelming tools I used were phaser.js and javascript.
Most of the ideas you find here are not original, but maybe you will find something that you have not considered yet. Here goes the list of 32 game ideas that can be finished in a short period of time.
1. Idle game
Idle games are very popular on the web and you can have a simple finished idle game with barely any graphics, proper buttons and counters very quickly using javascript libraries. It might be a good choice if you don’t have much experience in making user interfaces, as the game will mostly consist of just that.
2. Pinball
Pinballs were really great once, maybe they can still be today? Just remember to use an existing physics engine.
3. Single tower defense
You have probably seen such games, you are a tower or a castle, a single archer or a lone survivor of a zombie apocalypse where you just shoot at waves of approaching enemies while staying still.
4. Stationary sniper
This time there is no player character on the screen, just a targeting cross, and your victims.
5. Flying game
There is no shooting in this game, you just try to avoid moving obstacles while flying forward.
6. Match 3 game
These games have been popular for many years and still, a lot of them are being produced. You move an icon to match 3 of the same in a row. A simple casual game that is fun to play.
7. Combinations
Combine elements to create new ones, or discover cool effects by matching multiple items. It can also be less kid-friendly, like combining a metal bat with a head to get a piñata.
8. Puzzle game
Solve logical puzzles to escape certain doom.
9. Numbers game
Do some crazy stuff with numbers to get... more numbers. Or fewer numbers. Or put them in the right order to win, like in Sudoku.
10. Regular puzzle
Create interesting images by matching together shattered pieces of shapes.
11. Ball shooting game
Creating better FIFA or PES would be way too much work, but it would be possible to make a goal with the goalkeeper and allow shooting the ball from different places of the pitch trying to score.
12. Short interactive story
You might want to convey your feelings or a message to the world with a short text story and limited user interactions.
13. Choose your own adventure
Choose one of the options to move the story forward, the goal is to arrive at one of the endings. Just text here, no graphics.
14. Wordplay
Combine letters to words. Give few letters and let the player come up with a word in a limited amount of time, choose words in specific order to tell a story. Use an existing database to check the validity of words (for example WordNet).
15. Plant bombs
Carve the path or destroy enemies by placing limited bombs in strategic places.
16. Guessing game
Give the player some clues and allow him to take guesses. Maybe a detective game where scenario has to be recreated from some clues. Implement some helpers for reduced score if the player gets stuck.
17. Assembling game
Allow players to combine different stuff and allow them to feel the results. For example, create a spaceship or a car from simple building blocks and allow them to take it for a spin. Just don't go too overboard with customizations yet.
18. Ragdoll torment
Life is hard and sometimes you just want to take your frustration on something. Give your players something to punch, burn, kick, slash, break, or allow some creative ways to get rid of something or someone.
19. Ski jumping
You press the button to start sliding down, then again to jump, and try to position yourself to fly as far as you can and land on your feet. This can be tempting to put online multiplayer, but if you want that, you should try to finish the game with just hot seat multiplayer first.
20. Press button
Press some button and see the results. Then press another and see how both interact. Then press them in sequence to accomplish something.
21. Escape the ball
The boulder is trying to smash you, reverse pong where you try to avoid the ball with the platform, try to save things that are on the collision course of the ball by slapping them out of the way.
22. Creative destruction
Destruction as a form of art. Or something has to be destroyed so that something new can take its place.
23. Replicate to survive
Sometimes to survive one has to make a copy of itself to keep going.
24. Cursor is light
Darkness on the screen, lit only by the light moving toward the cursor, will you be able to avoid the terrors lurking nearby?
25. Preventing inevitable doom
There is an incoming danger that rises every few seconds and you have to defend yourself either by dodging, raising the shield, or making some quick decisions.
26. Billard
Hit the ball with a stick to push other balls inside the holes. You could put your own twist here by making different balls have different effects on the table when they are hit or go down the holes. Maybe table could have a unique shape, or holes could be constantly moving if you would want to increase difficulty.
27. Take care of a monster or animal
This one is probably more of a mobile game idea. Make the player take care of an animal by feeding, bathing or playing with it and see how it grows.
28. Ball control
Instead of trying to escape from the ball, you control the ball trying to hit as many things as possible.
29. Collector
Try to collect all items on the screen before either time runs out or something bad gets you.
30. Nostalgic old times
One of the first games I have ever played on a PC was riding a bike on platforms trying to catch them apples. It didn't make sense and it didn't had to. The game that is in my mind from the old NES console times even 20 years later was Kunio Kun series. I like them more than all the FIFA's I have ever played. Do you have an old game that is stuck in your mind and you could be inspired by today?
31. Cats
Cats are awesome, they are great at breaking stuff, chasing strings, licking themselves and apparently flying through space leaving rainbows in their path.
32. Education
You can make a simple game about garbage segregation, sickness risks, physics, chemistry, psychology, game development, color theory or any other knowledge that you consider interesting or worth having.
That's it. Remember that you don't have to stick to your genre choices after finishing the game. If you release a game in a month you will gain a tremendous amount of knowledge and experience. It will be much easier to motivate yourself when you attempt bigger projects with some problems already solved. I hope some ideas boosted your creativity. Thanks for reading and good luck with your game!