Shadow Abyss
Member
Based on what Mei has shown thus far Oro takes it with ease.
Mei's main form of attack is elemental spam and Orochimaru, being as slicky as he is, can take her streams of lava and water with ease.
You are also forgetting his defensive techniques and regenerative prowess. Mei's lava would never get past his Triple Hashomon and even if he is hit by one of her melting techniques he is able to regenerate his own body in multiple ways.
He is also very fast with Slithering Snake Mode and could easily distance himself from Mei's spot avoiding the range of her Boil Release. His Sword of Kusanagi can extend to incredible lengths making him able to hit Mei even if he is very far from her and combinated with his ability to hide underground he could even make a surprise attack out of that.
Using Sage Mode he could easily track Mei if she tried to hide herself on a mist and prevent incoming attacks.
And even after all that there's Manda, the giant snake that was able to completely shield Sasuke from Deidara's C0 and even chat for a while before his final death. That skin would make a stream of lava a total child's play and to make it worse for Mei it is able to shed its skin as well.
By the way, Mei has never shown the ability to drown a whole battlefield, you are making skills for her. The only shinobi that displayed such power with water was Kisame and even that is attributed to his colossal amount of chakra.
Mei's main form of attack is elemental spam and Orochimaru, being as slicky as he is, can take her streams of lava and water with ease.
You are also forgetting his defensive techniques and regenerative prowess. Mei's lava would never get past his Triple Hashomon and even if he is hit by one of her melting techniques he is able to regenerate his own body in multiple ways.
He is also very fast with Slithering Snake Mode and could easily distance himself from Mei's spot avoiding the range of her Boil Release. His Sword of Kusanagi can extend to incredible lengths making him able to hit Mei even if he is very far from her and combinated with his ability to hide underground he could even make a surprise attack out of that.
Using Sage Mode he could easily track Mei if she tried to hide herself on a mist and prevent incoming attacks.
And even after all that there's Manda, the giant snake that was able to completely shield Sasuke from Deidara's C0 and even chat for a while before his final death. That skin would make a stream of lava a total child's play and to make it worse for Mei it is able to shed its skin as well.
By the way, Mei has never shown the ability to drown a whole battlefield, you are making skills for her. The only shinobi that displayed such power with water was Kisame and even that is attributed to his colossal amount of chakra.