I'm very curious about the consequences of traps. For example, my favorite type of house trap is a pressure plated iron maiden style drowning trap. I have recently donated for the water perk (not instated yet) and was wondering if building such a trap and (even uninvited guests) if a guest gets trapped in it and dies would I be subject to ban?
Player traps are not allowed. Killing players in any non-PvP area is fully against the rules and punishable by a ban, and players traps are disallowed structures. The best way to protect your things is with our LWC lock system and not with traps in your house.
Also, I suspect that your trap requires sticky pistons, which are not allowed on ECC. In fact, you can't place normal pistons either.
So long as there is nothing forcing them into it, it is unable to be avoided, or "trapping" them in it, I do not think lava moats are player traps... If a user can only die to it by personally jumping in, I'm guessing it isn't a "trap."