Add the Yoriichi Type Zero in the game and have it as a training dummy, and kotetsu is the one who you talk to, to start the training, and as it says in the anime, the training lasts a full ingame day, and the doll cannot be stunned, and the training doll is very, very strong, and is adjusted person to person so it is always a certain amount stronger then you, to a certain point, and once you are increadibly powerful you can destroy the doll and get the rusty sengoku era sword inside of it, and after having it restored by hagunezka, you can get the strongest sword in the game
and by fighting the training doll you can get stronger, but its not very efficient (maybe, you can chose how xp works)
dracathereformed You’ve Reached Level 3