A realistic pit trap is a real highlight within a 3D-dungeon.
Of course you can use printed overlayers to represent traps but the real dungeon-feeling comes with 3D traps.
To create such a module by yourself you only need a sharp scalpel, a cutter-knife, some sandpaper, a ball pen, a set square, glue and approx. 20 minutes time.
Use the scalpel to make a horizontal cut into the gap underneath the floortile of the pit trap on the frontside of the module.
Now cut into the other gaps surrounding those floortiles which are the covering of the trap.
Make sure to leave the edge of the module unharmed.
Now use the cutter-knife to cut into the pre-cut gaps and through the floor of the module.
Keep in mind to leave the edge unharmed.
It´s better to make those cuts which are parallel to the edge of the module from the bottomside of the module. A set square may be useful. The nearest cut should be approx. 0.5 cm from the edge.
Now you can remove the cut block. Cut off the floor tiles of that block. Those tiles will cover the trap later.
Take the rest of the block and cut off a straight, approx. 0.5 cm thick piece from that side of the block, which was further away from the edge of the module.
Now glue that stripe back into the pit. The covering floor tiles will lay on this small pedestal and the unharmed edge of the module.
The trap pit is still bottomless. So take the rest of the removed block and cut off an approx. 0.5 cm thick piece from the bottomside of the block and glue it back to its former position into the pit.
We don´t need the remains of the block anymore now.
You can use a ball pen now to add some brickwork on the cut surface of the pitwalls.
Now move the floor tiles over the trap pit which is only visible when you look very closely.
The most important thing was to leave the edge of the module unharmed. In fact it´s more difficult to remove the block that way but it will increase the surprise for the gamers.
If you want, you can pimp your pit trap with spikes. The painted tops of some toothpicks do a good job.
We wish you a lot of fun with constructing and painting.