Eisen had a couple of different items in mind for the Wood-Giant's arsenal. There were of course its main weapon, the katana, and it's off-weapon, the wakizashi. But other than that, Eisen still wanted to give the Wood-Giant a couple of other items that it could use depending on the situation. In real life it would be pretty hard to upscale them like this, but luckily, Eisen could use enchantments and magic to his advantage.
One of the items that he wanted to make was a smoke-bomb. And it wouldn't be just any smoke-bomb, but one that was going to make use of Kirisho's mist. Usually Eisen wouldn't have been able to do that, it would have been impossible a couple of weeks ago, since Kirisho's mist wasn't a skill. It was part of her body.
But now, Eisen was able to make use of even abilities like that, as he already had with the brain of the Wood-Giant.
