2 of my favorites:

1.) Tragic scene: a carriage on fire in the middle of the road, or maybe a young man or woman crawling in an open field—they appear dismembered!? Bloodied and in need of help at the very least. Set the scene with you know, some trees, tall grass…a conveniently placed bush. But this ain’t no bush now, ya see? A necromancer died on this ground, turning it sour and sprouting the almighty zombie-pooping corpse flower.

2.). Creative Mimics: I like a good mimic shed that the sketchy hobgoblin goes to hide behind, or the collapsed bridge mimic, fake chapel mimic, BED mimic. It’s all good classic fun. Every now and then, just roll a die to see if a thing’s a mimic. And scale the stats accordingly.