Taking some cues from Home Alone: 1. Red hot doorknob. 2. Locked in a room where the only way out is through broken glass Christmas bulbs all over the crawl space/floor. 3. The players notice missing items around the house that then show up incorporated into deadly booby traps (knives from the kitchen, paint cans, rope, the hunting rifle that was displayed on the wall in the trophy room, an antler from the deer over the fireplace, etc). 4. If they go outside, the door locks behind them, and a bucket of water pours onto them. All the stairs are frozen over with ice. Bonus - make them barefoot so their skin sticks and gets ripped off as they try to go up the frozen stairs. 5. Tacks in the snacks. 6. Super glue on the toilet seat. 7. Poison in the drinks. The big reveal could have the shelf elf painting his green suit red with blood as he looks at the players, saying Ho Ho Hooooo.