This is an unwinable battle as Tobikage will cast Stone Skin at the start of the battle, making him invincible. The battle will continue until Jinnai uses Smoke Bomb and they flee from it.
This battle is a bit tricky as Tobikage fights along side with three clones of himself. If a clone is damaged, it will counter the attack before disappearing. Most of his attacks will damage every character for about 300 points of damage, except Assassinate, which will instant-kill a character. He also use Displacement after a while to replenish the clones and change his position.
As Tobikage uses Displacement gradually, randomly attack a target may end up with another Displacement being casted before his real body is revealed. It's recommended to use an attack that can heavily damage all targets at the same time. The party will get 3 counter attacks consecutively in exchange for his real position. Also, a White Mage with Curaja or two Dancers with Cure Waltz should be enough to keep the party healthy. Repeat the process until he is defeated.
This battle is scripted. It lasts until Jinnai uses Flash and he cannot be Knocked Out.