The Meaning of Life, the Universe, and Everything.
Me and a friend created a pvp minigame. It's called Dual.
2 players spawn in the center of any size of a arena and choose a team, it can be any color (example I have blue and red) and head to their colors tower. At the tower the players get dyed leather armor and a iron sword enchanted with knockback 1 and sharpness 1. They also get a potion of speed and instant damage. It is quite fun if you enjoy pvp like players on my server do :).
1. Make a big checkerboard pattern in the sky, but with holes instead.
2. Make a playing field below it in same pattern, but with a block with a slab on it.
3. Get a player to stay on land.
4.Get an admin to spam anvils.
Boat racing: Up to four players jump into boats and race through a long course with waterfalls, rapids, and occasional traps.
Death course: Set up a course riddled with traps that players must get through.
Underwater maze: A short maze that people need to get through before drowning.
Survival drop: Jump from an unbelievable height and try to land in a 1x1 pool of water.
TNT wars: Set up a floor with Redstone torches beneath every block. Players have an inventory full of TNT and need to kill the other players without blowing up.
My brother thought up a pretty neat one. Basically, you build 1 layer of sand with 1 layer of wood beneath it. Next, 1 layer below the wood layer, you build dispensers throughout the outer walls. The dispensers will shoot fireballs, burning the wood randomly, causing sand to fall. The objective is to avoid falling down. (Could be hard since you can't see beneath the sand.)
I've gotten my game ideas from watching AH Things to Do:
-Minesweeper: Instead of TNT and sand, I used dark grey wool as the top layer (can be destroyed quickly with shears without harming their durability) and different colors of wool for the mines and numbers on the layer underneath (very easy to move around to replay, again thanks to shears)
-Shooting: I have two of these next to each other with a redstone timer inbetween. The first is Mooshroom Hunting- mooshrooms in minecarts going back and forth. it's a pain to get the Mooshrooms in the carts, unfortunately! The second is Shooting Gallery, where you hit small paintings off walls. There are hoppers in minecarts going back and forth underneath so none get lost
I also have a secret room maze, not sure if that counts? It's more of a puzzle, but very fun to build and go through!