After the ante 1 boss blind DNA show up on the shop. After the ante 2 round 5 ( just before the ante 2 boss blind) there is a spectral pack which contains ankh to duplicate DNA. I do not remember the exact round or shop, however invinsible joker is avaible before the ante 8 ( It coppied the dna in my run). Also, showman appears after ante 8 multiple times. I have made it to the ante 16 pretty easily.