Get the adventurers in a room where there are 4 chains that they can grab onto to cross over a huge pitfall. There is a door on the other side.
Place all of the chains close enough next to each other that holding onto one and reaching to another is a viable option to remove athletics or acrobatics for a jump (meaning only the original jump check would matter)
If the first and second chain are grabbed at the same time it completes a circuit and causes electrical damage and a bullrush check against the player to knock them into the pit.
The third chain is magically greased, so the players will need to jump immediately, jump passed it, or succeed on a ridiculous check to grab or be knocked in the pit.
The fourth chain is an illusion. So spot that, or any likely attempt to grab it will knock a player into the pit.
Behind the door are three ramming magical charms which will be triggered on opening the door, walking through the door, or failing the check to disarm the door. These bull-rush checks should be high enough to knock someone into the pit.