so pistons should be able to add spikes to make traps BOOM TRIPWIRE SPIKED PISTON YOUR DEAD and maybe they could have turret? like guns on the end of them or extensible swords. also they could be used to create TORCHES CHAMBERS. since the spikes would come down on the players heads and maybe they should have a special torches effect you know how some effects that are here already are like strength poison hunger well there shod be a torches effect that makes you deal less damage and makes u take little damage and you get torched by being in a room smaller then 5 blocks and having a spiky piston hit u what do you think.
Other than the potions thing, which can be done with dispensers now, spiky pistons were originally planned, then dropped in favor of sticky pistons which could be used to move a spike block around. Spike blocks have been planned for some time now, but Dinnerbone is not sure of how to implement them.
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