As we know the requirement to gain the Rinnengan is if the Uchiha has both Indra and Ashura DNA or chakra. Obito body has Hashirama DNA, then later Obito gained Madara Rinnengan.
So basically Obito had Hashirama DNA (Ashura) along with Madara Rinnengan (Indra), which obviously contain Madara DNA.
Imagine Obito with his MS fully evolved to Rinnengan, he would be like Sasuke using his MS jutsu along with Rinnengan.
So basically Obito had Hashirama DNA (Ashura) along with Madara Rinnengan (Indra), which obviously contain Madara DNA.
Imagine Obito with his MS fully evolved to Rinnengan, he would be like Sasuke using his MS jutsu along with Rinnengan.