YMMV / Touhou Kikeijuu ~ Wily Beast and Weakest Creature

• Game-Breaker: Marisa-Wolf and Youmu-Wolf. Their damage output is exaggerated, blasting through bosses with incredible ease. Even Mayumi hiding behind her haniwa soldiers won't do much to protect her, especially against Youmu. Their enhanced shots even give them stage utility, with Youmu's slashes reaching farther up the screen and Marisa's missiles creating larger explosions that excel at taking out packed enemy formations.
• Good Bad Bugs: Carrying over from the previous game, using a bomb on the Extra Boss's survival spell will make a health bar appear, allowing you to clear the spell by shooting it down. It must have been a coding oversight ZUN really couldn't fix, because in the next game, survival spells have the boss go offscreen altogether.
• Low-Tier Letdown:
  • The eagle spirit in general can be this, because most stage sections are so simple that the stage utility provided by enhanced unfocused shots isn't all that relevant, compared to wolf's stronger focus being great against bosses and otter's Smart Bomb perks being good against everything. However, Youmu-Eagle in particular is widely considered the worst shot type in the game. Not only are her wider unfocused shots not very strong or useful, ZUN made a typo when coding her Charged Attack, making it so weak that boss fights become a pain to get through.
  • The otter spirit, while agreed to be useful in the main story for its bomb related perks, especially in higher difficulties, becomes this in the Extra Stage, due to the boss having a bomb shield as per series tradition.
• Salvaged Gameplay Mechanic: The Animal Spirit system is notably similar to the UFO system from Touhou Seirensen ~ Undefined Fantastic Object, but rectifies what made the UFO system so frustrating. For one, the Animal Spirits stick on the screen for much longer than the UFOs, so you're less in a hurry to catch the items. Second, they don't immediately go away the moment you reach the boss of the stage. In fact, they continue to bounce around and change colors even during pre-battle dialogues, making it a good chance to gather the spirits you need. Finally, it's just a lot less necessary to collect the proper combos. While collecting the wrong UFO can screw your resource gathering, you can enter Roaring Mode any time you collect five spirits no matter the combination. Collecting the proper combinations gives you a Super Mode and makes it last longer, but it's not necessary for gathering lives, bombs, or scores.
• That One Level: Stage 4 and the Extra Stage can be this for a lot of players due to the notoriously bad visibility making it possible to mess up or get hit through no real fault of your own. When people complain about ZUN making the background the same color as the bullets, they often refer to these two stages. Odds are your shots are red as well, which doesn't help either.
• Viewer Species Confusion: The otter spirit is sometimes mistaken for a hamster.