It is about an unnamed player character who wakes up in the dark forest and is welcomed by their few surviving brothers and sisters as "The Last Captain", destined to pilot the last hallowed ship they have through the river in order to reach the World Tree, and seek an audience with the titular deity who lives at its top, as they believe this is the only way to be saved from the monsters overtaking the forest.
Like their previous game, Gloom, it is an (almost) entirely black and white game with dark storytelling. But whereas Gloom tried to adapt the gameplay of Dark Souls to the Side View 2D and the Roguelike structure of The Binding of Isaac, The Treehouse Man is more of a cross between Undertale and an (easier) Darkest Dungeon, as it has the Turn-Based Combat with real-time dodging during the enemy's turn of the former, while each stretch of a river acts as a mini-dungeon like in the latter.
Tropes present in The Treehouse Man:
- Airborne Mook: There's a creature that is basically a floating head in a cage, and it attacks by flying very close to the boat and then sending out multiple spreads of three shots through flapping its cage door open. Alternately, a particularly devious attack has him fly pretty much straight at the player and then, if they dodge it, fire a ring of shots from the corner of the screen behind the boat.
- There's also a more conventional floating witch-like opponent. She won't move, though, and instead will simply gesture with her hand to generate several orbs around the player, which will then slowly close in for them. Either that, or she causes smaller, faster-moving orbs to appear from multiple points behind the boat.
- The platforming sections feature winged head monsters that repeatedly spit orbs from a point out of your reach, essentially acting as invulnerable turrets. You'll eventually encounter them during the turn-based combat as well, when they are hatched from a giant egg during a boss fight.
- Then, a later stage features enemies that can only be described as floating tentacled hives, and which generate electrical attacks near you.
- All for Nothing: Played with. The arguments about the intentions of The Treehouse Man, including the voiced by The Betrayer right before his battle, are moot because by the time you reach The Treehouse, it is empty. The overall journey, however, wasn't, because then the player becomes The Treehouse Man, and uses his power to cleanse the forest of monsters to save his group.
- Amplifier Artifact: There are runes, which a painter character can draw on your boat if you provide him with pigment.
- Blob Monster: One of the enemies encountered is a really large one. One of its attacks is to spit two dark orbs (not white ones, like most damaging attacks) which then land on the decks and turn into typical small slimes, which will slide back and forth along the deck. You cannot do anything but dodge them until they dissolve away after several goes.
- Bloodless Carnage: The game has no visible bloodshed, but comes up with a disturbing alternative of its own. Whenever you encounter enemies while travelling on the river, they'll often be placed on the tree branches, or floating in mid-air. Killing them results in their lifeless body simply dropping into the waters with a splash.
- Bullet Hell: The tougher enemy patterns will easily send out dozens of projectiles onto the screen, while you only have a limited space to dodge on your boat. And as expected, the Final Boss battle takes this to the next level.
- The Cameo: The Clown who holds a bunch of balloons was seen earlier in Gloom. However, his role there was limited to telling (an admittedly morbid) Lightbulb Joke in The Common Dream, while he he's a full-blown companion,
- Combat Tentacles: A late-area octopus monster attacks with these from underneath the boat.
- Classy Cane: Averted with one of the children in the group you are "baptized" into. He lost his leg earlier on, and props himself up on a mere untreated stick, with branches still intact.
- Creepy Crosses: The Betrayer has a cross emblem across his chest, and his hair also seems to have somehow been braided into crosses. This rather fits his whole role as a Dark Messiah.
- Then, the second stage of his battle has cross-shaped rays fading in from the background as one of his attacks.
- Critical Existence Failure: Being a hitpoint away from death does not hamper either the player or the enemies.
- Critical Hit: Your attacks can score these and deal extra damage. Lilli's presence raises your chance of scoring these by default, as her calming music improves your concentration, and therefore, accuracy.
- Dark Messiah: The Betrayer believes that his people no longer have the right to survive after what they have done to the forest in the past, and so he finds it right that they should all die to the monsters, while he drowns anyone attempting to reach The Treehouse Man in a pool at the bottom of the tree, and intends to sacrifice himself to the forest once he's the Last of His Kind.
- Defeat Equals Explosion: The bomb-generating creatures blow up upon death.
- Deliberately Monochrome: The game is mostly black-and-white, though it is not as strict about it as Gloom, and occasionally includes spot color like the red eyes of the enraged enemies.
- Energy Ball: Nearly every enemy attacks during their turn through shooting whole patterns of these, which you must dodge in real time. The attacks of your own boat also appear in this manner, as they are literally fired from the boat's lanterns.
- Final-Exam Boss: First, many of the attacks in the first two stages of the Final Boss are enhanced versions of the attacks you faced before. Then, did you ever wonder what was the point of the seemingly identical optional platforming sections, where you climb Temporary Platforms extending up into the sky to claim a chest, while dodging shots from the airborne Invincible Minor Minion? Welcome to the fourth stage, which is all about climbing these (thankfully permanent) platforms, while the Final Boss keeps shooting at you as its last hurrah.
- Flash of Pain: The edges of the screen flash white whenever the player loses a heart.
- Gameplay Ally Immortality: The companions on the roof of the boat are unhurt by any of the enemy orbs flying around.
- Guilt-Free Extermination War: In spite of possessing gameplay inspired by Undertale, the game hardly shares its worldview on these matters. In fact, the ending shows a montage of all of the monsters getting exterminated as a result of whatever power your character gained through reaching The Treehouse.
- Heroic Mime: The player character never speaks.
- Hyperactive Metabolism: You can restore health through eating Gosberries.
- Imaginary Friend: One of the unlockable companions is this, and his presence grants you an extra imaginary heart.
- Inexplicable Treasure Chests: These can be discovered on some of the tiny islets in the river.
- Kill It with Fire: The Igniter weapon sets targets on fire for continous damage over the next 4 turns. After an upgrade, it'll also deal triple damage to the already burning targets.
- Limit Break: The enemies become stronger after they get enraged, which usually happens when their health goes down a lot.
- Magic Music: Lilli's flute music passively raises your Critical Hit chance. She can also play a melody that'll weaken all the monsters on screen.
- Miss Exposition: As your first companion, Lilli is the one who explains the basics of gameplay during your first sailing.
- One-Winged Angel: The Betrayer turns from a human like you into a tree thing that has six lanterns on its branches, and can use four of them, plus its own multi-eyed head, in order to launch enormous barrages of attacks at you. Then, when that stage is defeated, it turns into a large floating circle with the same head, and 10 short tentacles, each holding a lantern. Moreover, that battle is now real-time.
- Platform Battle: The second stage of the battle with the Betrayer is one, as you lose your boat, and instead dodge his attacks by jumping on the platforms suspended in mid-air.
- Played even straighter during the third stage, which is real-time and you can only fight back by activating the attack buttons that appear in one of several spots on the platforms.
- Practical Currency: The forest folk shopkeepers' trade with cones.
- Rare Candy: Hallowed Hearts raise the maximum health by 1. Correspondingly, merchants sell them for a whole 250 cones - when a single trip down a river section nets a few dozen of them.
- Red Eyes, Take Warning: The enemies' eyes (and mouth, somehow) turn red when they get enraged, and will do much stronger versions of their normal attacks.
- Sad Battle Music: The Final Boss theme, Apotheosis
, is very subdued and melancholic. This is even though you have little reason to pity him. - Sequential Boss: Every boss has at least two stages.
- Shock and Awe: The hive enemies in one of the later stages generate ball lightning near the player, which then bursts into several smaller projectiles.
- A larger version of these enemies first encases the player into a box of electricity, then forces them to dodge two ball lightings within it.
- The Final Boss can also deploy the electrical attacks, amongst others.
- The Smurfette Principle: There's only one girl amongst the forest denizens who greet you, Lilli. She's also the only one brave enough to accompany you on the mission, and she becomes your first companion - and remains the only female companion throughout the game.
- Spread Shot: The typical enemy fought in pairs often sends out a classic spread of three from his mouth. However, he can also spit a single orb that'll travel upwards, and then splits into a spread of five that rains downwards.
- The floating head in a cage monster also fires a spread of three, several times per turn, and while flying up close to make it harder to dodge.
- Super Spit: Most of the early enemies spit their orb attacks from their mouth.
- Temporary Platform: These appear during those of the platforming sections.
- Unexpected Gameplay Change: The final battle is against The Betrayer, who is a human with a ship of their own. The gameplay is still traditional there, but then he destroys your boat at the end of his first stage, and you fight his One-Winged Angel stage on land, deploying one attack from your powered-up lantern while having to dodge a myriad projectiles during each of his turns.
- Then, it says Everyone's turn, and the battle against the third stage becomes fully real-time.
- Then, once that stage's health runs out, you are in a huge platforming stage, where you can't do anything but climb and dodge attacks from the boss.
- And then, you finally reach the top of the Tree and it says "Your Turn", and you realise the entire climb up the tree while getting shot at acted as one last, enormous Betrayer's turn. Your one attack instantly finishes it off.
- A minor example occurs earlier on, when the toucan beak-headed enemies in the second stage demonstrate their attacks. The first creates a bunch of bouncing black blobs, which are moderately difficult to avoid. The second one simply generates a black turret thing at the top of the screen which continually shoots in a straight line downwards, and so is trivial to avoid. Then, the enemy's turn ends, and you suddenly realise that the turret did not disappear, and continues to shoot throughout your turn, which is a real nuisance if it ends up spawned right where the controls for your weapons are.
- Villains Act, Heroes React: The gameplay is often like this, as during combat, you are limited to a choice of two main attacks (which you can upgrade and swap out at camps), a companion ability and the emergency attack from the furnace which has a multi-turn cooldown, and all of this happen very quickly once activated. In contrast, the monsters invariably fire long barrages of projectiles during their turn, forcing you to react keenly in order to dodge them.
- The second One-Winged Angel form of the Final Boss battle takes it to its extreme: because your power gets boosted, you only need to land five attacks in order to bring it down. However, each of your attack is followed by the boss acting five times during their turn, activating a sizeable attack sequence every time.
- This is eventually revealed to be true for the story as well, since it was The Betrayer deciding his people did not deserve to live and drowning most of them himself that put the survivors in such a dire position and at a risk of getting wiped out by the forest's monsters, which is what necessitated your quest to reach The Treehouse Man.
- What Happened to the Mouse?: The ending montage shows that the monsters were all exterminated, and that your brothers and sisters from the start of the game are safe, but it's unclear if any of your companions survived after the Betrayer sank your boat.
- Where It All Began: Invoked by the Final Boss:The Betrayer: You know, this is where it all started. This is the basin where I drowned countless of our brothers and sisters. My journey has gone full circle. Where it has started, is where it must end.
- Wingding Eyes: The Blob Monster enemy will have its eyes turn to crosses when defeat, right before it sinks to the bottom.
- World Tree: Reaching one to contact The Treehouse Man who lives at its top is your goal. Then, it turns out there's no one in the Treehouse, so you become The Treehouse Man yourself instead, and save your people with the power.
