Edo Tensei-this technigue is too haxed and uses someone else's power(different from jinchurriki's and obtained powers like sharigan etc..). We've never seen Tobirama do it, Oro only used it once for people he cant use again , and Kabuto has alot of complications also. If hes in a fight with Third Raikage, then he cant use the third's edo. If he is fighting Nagato then he cant use Edo Nagato. Not to mention if he fights a edo(in a thread or so), he wins automatically because all he has to do is say "release!" There are too many loopholes.
Gedo Mazou-Due to its different positons in power, there are too many loop holes and arguements that arise because if this technigue. Sure Nagato and Tobi used it, but Nagato had the 0 tail version while Obito used the 7 tail version. Alot of NB members argue that Nagato can use the 7 tail version but he never used it. What if Nagato fights Obito? Who gets the Mazou as a technigue?
Six Paths Of Pain-This only applies to Mobile Nagato. Some NB members say that Nagato can fight along with his 6 bodies which is false. Its either Nagato OR the Six Paths of Pain.
Izanami-The most useless technigues in the history of Naruto. This move CAN be considered but its pointless because of how useless it is. Alot of Itachi fans in general say Izanami-Izanami-Izanami like its useful. It only works ob people who dont know who they are/ are lying to themselves and that makes up for like 0.67% of the characters in the series. The only person it worked against was Kabuto and even Kabuto can kill Itachi before it activates.
Talk-no-Jutsu-This technigue is just haxed up the ass. Alot of people has fallen for this technigue that it should be declared forbidden but it doesnt matter. Alot of people subconscouisly abuses it anyways.
Edit:Koto Amatekami-This technigues has never been successfully used once in the series. Shusui and Danzo never used it and Itachi only used it himself because HE HAD TO. He was saving it for Sasuke and thus will never use it in battle.
I think I missed some but I cant think of the rest.