Laser tripwire:
When you place two laser tripwire blocks within 5 blocks of each other with no blocks in-between, it spawns a laser between the two blocks, and when you walk through it, the two source blocks give out redstone power.
How it looks like:
When you walk through it, it gives off redstone power:
Keypad:
When you place the keypad block, the first time you right-click it, it opens a setup screen which allows you to setup your passcode for that specific keypad. After you hit that button/ right-click the block after that first time, it allows you to enter your passcode. Once you type it in correctly, it closes the GUI and gives out redstone power for 3 seconds.
How it looks like:
The setup screen:
The keypad screen:
An active keypad:
Mine:
After placing the mine, any entity that walks on it (besides a creeper, cat, or ocelot), including players,will
automaticaly get blown up. You can not place the mine on flowers, cactus, glass, or air.
How it looks like:
The explosion: