Booby trap only should work on personal claim, so no trolling from players planting them everywhere. They should attach just like how locks attach to things, can't be seen by other players nor custom clients only to those who built/crafted them can see like a icon in toggles that there is a booby trap there including those who are allowed to enter the personal claim. The booby traps could be attached to building entrances and exists, so 2 traps per door for enter and exist, so keep it balanced no 10 traps for 1 house door, but let's make it fair for Hermits by making it so only 2 can be attached for every entrance of the building under the personal claim even the cellar.
Grand list of posibilities, boody traps for containers when being opening the container, boody traps for trying to cross personal claim of either direction (not sure if only put 1 booby traps for the personal claim line, or make it so for all 4 sides east, west and so on), booby traps for the ground so for crops or specific tile on personal claim (can't be at the edge of claim so no boody traping every tile on of personal claim, but I guess every spaces of when first personal claim is built that many tiles apart which should be enough for couple crop fields and beeskep too, so the intruders could play mine sweeper.), booby traps the buildings and liftable structures (hopefully this doesn't make a problem of double booby trapping containers).
The effects of booby traps, each should give a nasty wound (of course can be treated, let's be fair) so go nuts Jorb do the Dio wreeeeeeeeee XD, the damage should depend on quantity used and quality of items so for example placing a booby trap made from rope and pile of rocks on a house door entrance would cause damage let's say 10 rocks of quality 10 so that's 100 hard hitpoints so wound let's say head smashed it, cracked skull and concusion, (maybe not on that extreme, but as example to start).
Images of said booby traps that could be used in game.



Feel free to suggest more booby traps, their placement and potential wounds from either burning skin from tar and fire, pierced flesh from shooting arrows and so on. Let Hermits have somewhat of a defense when they are logged out, but not go to crazy keep it balanced.