This chapter would be just fine if there were some level of inate ability/knowledge to your ninja magic but after chapters and chapters of ninja school and training, this quick mastery of both the phasing ability of the sharingan and control over the zetzu to use the wood technique just seems... convenient.
Anyway, I'm certain after killing all these ninja, Obito is totally going to tie up Kakashi and wait for him to revive himself so he can get an explanation before he kills him for killing Rin and not do something utterly stupid like flee the scene suspecting that he knows the whole story. Right?
A simple souvenir of someone's kill
And like the sea
I'm constantly changing from calm to ill
Madness fills my heart and soul as if the great divide could swallow me whole
oh, how I'm breaking down