Musashi Gundoh TV 13
So, this episode starts off with a flashback to how the ninja kid (voiced by Yuu Kobayashi) got turned into a monkey (voiced by Yuu Kobayashi) after he was caught spying on LEONARDO DA VINCI god knows how many years ago. Not longer after he's done, the rest of the gang finally arrives sans the woman from the earlier episodes with the magical transforming gun. This includes the ninja-turned-monkey-turned-ninja's equally retarded looking brother (also voiced by Yuu Kobayashi).
Not long after that, the two duke it out in some poorly animated fight involving leaves and a log. Eventually there's a campfire scene ending the episode with some weird swamp like monster summoned by flags raising out of the ground. The background then changes to some weird green & purple photoshop accident while the monster turns into a large hooded man. The man then turns into a gigantic Tiger (Unfortunately, neither of these two were voiced by Yuu Kobayashi).