Episode 173

The End of Mōryōmaru is the 6th episode of InuYasha: The Final Act.

Plot
InuYasha and company arrive at a tree outside a village, having been told it's a demon/human-eating demon that had been sealed long ago. However, when new buds started appearing on the demon's branches, they asked a monk for help, only for the demon to swallow him; they've been too scared to go near it since. Wondering what could have caused it to come back to life, Kagome notices Naraku placed a Shikon shard in it. Inuyasha doesn't care, decided to fell the demon with the Wind Scar; however, the attack is blocked by Naraku. The tree comes to life, saying that it hasn't had demon in a long time; it pierces Naraku's barrier. Naraku up roots the demon, saying he likes it; the tree demon is confused as he's going to eat him. However, Naraku turns the tables by abrobsing the demon into himself. He escapes.

Meanwhile, Kōga is trying to track down Mōryōmaru but instead runs into Kikyō and Kohaku. Kikyō wants Kōga to give up his shards so that she can go through with her plan, and she points out how the shards in his leg haven't been obeying him lately. Kōga, however, refuses to give them up and continues after Mōryōmaru.

At around the same time, Moryomaru and Naraku run into each other, with the end result being a miasma so powerful,. it kills all life in their immediate area. Naraku taunts Moryomaru, saying he knew that he would come for the Shikon Shards in his possession; Moryomaru says that Naraku only has him beat with the amount of shards he has. They begin fighting, with Moryomaru blowing Naraku to pieces; Naraku says he'll absorb Morymaru, only for the opposite to happen. With most of the Shikon Jewel now in his possession, Mōryōmaru's next goal is to go after the remaining shards, and, watching from nearby, Kagome realizes that this means the ones possessed by Kohaku and Kōga.

As Kohaku and Kōga are both nearby, Moryomaru targets Koga first; hoping to test out his new powers. With the arrival of Inuyasha's group Kōga and InuYasha try to work together against Mōryōmaru, but they're not able to accomplish much. Inuyasha quicklu discovers his Tessaiga is useless against Moryomaru's armored shell as Mōryōmaru manages to capture Kōga in his diamonds in preparation for taking his shards. The Infant thinks to himself about victory, only to be surprised by Naraku's face staring right at him.

The reason Naraku ate the tree demon was to gain it's barrier-piercing powers to reclaim his heart. As Naraku is taking over his armor, the Infant prepares to leave, only to be stopped by Naraku. The Infant says he's willing to die if it meant killing Naraku as well, willing to choose death over re-absorbtion. Having absorbed Moryomaru's insides, Naraku destroys the haku puppet's out shell, revealing himself with the Infant held captive with barrier-piercing vines and Koga still trapped in the diamonds. In order to free Kōga, Kagome fires an arrow at him, succeeding in breaking him free of Naraku.

Miroku opens up his Wind Tunnel to suck Naraku in. Unfortunately, this means that Miroku also sucks up tons of Naraku's miasma, putting his own life in danger; he begins to bleed from his eyes and mouth due to how much more powerful Naraku's poison is. Miroku is able to suck in the Fuyōheki (allowing them to find Naraku with ease now), but because of the danger, InuYasha closes the Wind Tunnel before Naraku himself can get sucked in, thereby allowing him to escape. Naraku taunts Inuyasha for doing so as he almost got sucked in; he then flees with his recovered heart. In the aftermath, Miroku is barely still alive and Kikyō tries to treat him.

Trivia

 * This episode also marks the death of the Infant; reabsorbtion into Naraku eliminates his individuality.
 * Also the Fuyoheki is destroyed; Miroku managed to suck it into the Wind Tunnel.
 * The Wind Tunnel sent out what appears to be an electrical discharge, from sucking in Naraku's miasma.
 * This marks the last appearance of Naraku's post-Mount Hakurei look.