Powered Pistons
for some reason, pistons sometimes power other pistons...
reproduction steps:
- place 2 piston facing left
- place 2 pistons in front facing up
- place repeaters facing pistons
- place Redstone behind the repeaters
- place something to activate it (lever preferred)
at least one of the pistons from step 2 should get powered, if not you probably need to redo the steps