Genetic manipulation

[Obak]

I am looking to have my character create new breeds of creatures, spiders that inject narcotics instead of venom and selling it to decadent drow, making it all the rage!
Anyone know of any technique of doing this using magic/feats?

[Jormengand]

Epic spells with the Conjure, Life and Fortify seeds can create entirely new creatures. Such spells usually require huge numbers of casters and/or have high XP costs, though (For example, the spell Origin of Species: Achaierai burns 10,000 XP and needs 32 people to cast it, 22 of whom need to be fairly high level. Though, it's a pretty badly designed spell, and the mitigating factors could be chosen a bit better).

Probably not what you're thinking of, but the best I can think of.