How to get X rank on every boss: A combat guide on a visual novel game by Aqua/Clover (call me either :3)
Each boss fought in this guide was accessed through the boss selection menu. This can be accessed from the main menu by selecting Start and then the "Send me to the Fights!" dialogue option. I say this because if for some reason there are any differences between the boss fights in the full game and the ones in the selection menu, these strategies may not work.
Everything I say here is not absolute. These strategies are not the only way to get X rank, nor are my recommendations, but this is just how I got X rank personally. I know this may seem obvious, but I want to be clear that you don't need to min-max a visual novel's combat system to enjoy it.
Set-up and optional cheesy stuff
You may want to re-spec your player character to better fit the role they'll play in the strategies. My main stats are Brains and Charm. If you are interested, here is how you get my build. First open the start menu and select "I want to change some gameplay things." Then select "I want to redo my stats!" Now for the questionnaire select the following options: "It's less about the drink and more about the presentation." "I've got noodle arms..." "Taking the necessary precautions to prevent my mirror doppelganger from replacing me at night." "I'm never afraid to ask questions." "Wandering around town!" and finally "A ghost!" These answers will give you a stat layout of -2 Brawns, +3 Brains, +1 Hustle, 0 Guts, +2 Charm, and -1 Occult. There is one more optional step: Using the Lemon Squeezy dice. They are the easiest dice in the game and will drastically increase your chances of an X rank, but I DON'T RECOMMEND USING THEM because it's less fun. Another thing that I DO NOT RECOMMEND but is available for those who don't care is that any and every scripted attack can be rerolled by going back in dialogue on any dialogue after the dice gui disappears but before the dialogue ends; in the same line of thinking you can use the back button after seeing the damage of a non-scripted attack to decide if you want to use Karma to reroll. A final tip I don't consider cheese is when your super close to winning you can exhaust your party members or even let them die in order to conserve turns as it won't matter if you win before you're punished.
Base game bosses
Madhouse: Your most important party members are Jamie and Atlas. Jamie's Spirit Blaze is infinitely better than their Skull Cracker and it will be your main dps. Whenever you have 3 or more stamina you'll usually be using this move. Atlas main role is to spam Lore Dump and lock Madhouse from ever getting a turn unless you want him to. After using Lore Dump the strategy becomes pretty loose. MC should only really use Focus and Cheer (on Jamie) but if you make a mistake you can use Heart Out to stall an extra turn. You should be using your extra turns from Lore Dump to restabilize your resources or set up a powerful attack. Stalling forever with Atlas is an effective strategy but it wastes to many turns. In order to achieve X rank you should make use of Taro's Tuna Defender to tank attacks whenever you feel comfortable. Taro's only other use is to use Pounce to restabilize your stamina economy. Don't be afraid to use Cheer on Jamie even if they are at max HP.
Mr. Walker: The strategy for this boss is much simpler. Your first goal should be to murderlate Mr. Walker. August can easily do this with Onslaught. Once Mr. Walker is down, Lantern will waste it's turn healing him. Whenever Mr. Walker gets up, use August to get him back down. In order to keep August's stamina stable, whenever Mr. Walker is revived and August can't use Onslaught without exhausting, use Sleight of Crowbar as a budget option, or if Mr. Walker is low enough you can use Bite Back. Keep in mind Bite Back only activates once even if Mr. Walker attacks more than once. Oz is your main attack against Lantern. Use Silver Stab and use your Karma frivolously in order to proc his 11+ effect. You should use Bandage Wounds if you are out of Karma even if everyone is full HP because the effect is so potent. Since Oz will almost always be focused on Lantern and August is focused on Mr. Walker, MC's job is clean-up. MC should take action in these scenarios: in order to keep stamina levels stable, in order to finish off Mr. Walker and conserve August's stamina, and finally if you are confident you can squeeze in an extra attack against lantern without consequence. Usually you want to use an Sleight of Crowbar or Focus. If you make a drastic mistake, stall for energy using Glare and/or Howl.
Madhouse vs. Jamie: This strategy is a loop of moves, and the loop should rarely ever be broken. Use your better judgement before differing from the cycle; use only Cheer Madhouse or Idle only when out of Karma if so. Here is the gameplay loop: Kinesis, Not The Face, Noxious Fist, Heckle, Not The Face. Generally, don't break this loop even to heal Madhouse the first time because you can probably pass the Fright For Your Life! check if you've been conserving your Karma. I recommend also using Karma to succeed the Silver Grasp check if need be. Once Jamie is on his last life and is low enough, you might want to exhaust Madhouse for an extra Kinesis if you know it will win you the battle in order to save turns and guarantee X rank.
Madhouse EX: The same strategy for Madhouse works here as well, albeit it is less forgiving. Consider using Taro's Tuna Defender to get her under 5 hp and buff Pounce if you are feeling anxious about getting the X rank in time.
Madlas EX: The Madhouse strat works here as well, but you can only use Taro's Tuna Defender to tank hits. This means waste as little turns as possible on the defensive. Taro's Jeer is effective at keeping Madlas EX's attacks at bay. MC should spam cheer on Jamie who should spam Spirit Blaze.
Mist(er)walker EX: I actually consider Mistwalker EX to be easier than Mr. Walker because you have Jamie. MC is almost entirely useless in this battle and is only good to balance the stamina economy. Other than that use August on Mr. Walker, Oz on Lantern, and Spam Spirit Blaze with Jamie as it hits all targets. Prioritize using Jamie's attacks before others so that Jamie isn't wasting any stamina. You should probably reset the boss if Jamie's Spirit Blaze + August's Onslaught does not down Mr. Walker in the first round before Mr. Walker attacks.
Jamie EX: Literally the exact same move loop again works here, but this time there's no MC who was borderline useless in the first place. DO NOT DEVIATE FROM THE ATTACK LOOP IN ORDER TO GET A GUARANTEED WIN.
Robo-Atlas: Once again Jamie shines as an excellent attacker. Jamie should spam Hellhound Hurricane this time however. Start off the battle with Sabotage and then Inescapable Flex. The order is important so Atlas regenerates stamina. RESET IF YOU FAIL IN THE BEGGINING SEQUENCE as using Karma raises Robo-Atlas' difficulty and failing the move is detrimental. In this fight, most of the characters are actually useful for a reason or another. Prioritize attacks with Jamie so they can get to regenerating stamina faster. This fight is actually very forgiving because Jamie, Atlas, and August all have a stalling move allowing the other's to regenerate stamina; Jamie's even costs Karma which allows it to be used back to back if you really mess up. Though you should prioritize Jamie's Hellhound Hurricane, if you want to finish Robo-Atlas in a timely manner, you should use KinesisOmega beforehand. MC is useful for the move Jersey Tango which is a multifaceted high damage move and a better focus. August is mostly useful because he is used in Hellhound Hurricane, but his other use is to stall for stamina with Howl and if worst comes to worst Bite Back.
Also Madhouse and Oz are both incredibly attractive for entirely opposite reasons lol let me date them already... PLEASE PLEASE PLEASE PLEASE PLEASE PLEEEEASE!!!