>>49594852You could make it a hypermetamorphic bug to trick people, these go larva 1 -> larva 2 -> adult. Strepsipterans for example have a "speed form" larva with large eyes that finds a host and morphs into a bulky "feeding form" larva that parasitizes it, which later becomes either a winged male or a flightless grub-like female. Some flies are the same, except they have a tough "infiltration form" that cuts a hole into the cuticle of a spider, and a "slime form" that can leak into that hole.
Strepsipteran females look like larvae, so you could fool biologists by disguising the mid-stage as the adult female. Hell, you could make it a Combee-like thing too. Only the female evolves at level 10, and then again at level 40 into the wyrm-form Bug/Dragon, while the male evolves directly at level 40 to the winged-form Bug/Dragon, making it a double surprise for people who raise the male.
>>49595549My wish for Bug/Dark is a nest-infiltrating rove beetle. These are ridiculous, some can sneak into termite nests because they have an entire decoy termite on their tails. And they're pretty evil because they feed exclusively on termite eggs and larvae.
Make it a two-stager with low stats, but give them Disguise. The first stage has a crude "sock puppet" of a Weedle on its back, the second has a much better replica. Make the Pokedex mention that they use their decoys to infiltrate Beedrill nests and feast on defenseless Weedle. Alternatively, give them multiple forms that each imitate a different early bug, so you have a Caterpie form, a Wurmple form, a Sewaddle form etc. I'm thinking Stapilfer and Rovenous as names.