Here is another installment of exTRAPaganza, our Thursday over-the-top trap series.
A huge jack-o-lantern is in the center of the room. Light emanates from it, and what looks to be golden seeds fill it. It can be climbed, and the heavy top removed or hacked through.
However, the top is precariously placed. Unless a hard Dexterity check is made when moving it, it falls into the pumpkin. If the pumpkin is hacked, pieces fly into the pumpkin and seeds spill out.
Either way, it causes an explosion, and seeds and pumpkin fly everywhere. Those in the room take heavy fire damage from the explosion and fall prone. A hard dexterity saving throw reduces the damage by half and negates the prone effect.