Ibb & Obb

Most “co-op” games are single-player games with a second controller attached. Ibb & Obb is a rare exception. It is built from the ground up so that neither player can progress without the other. Swedish studio Sparpweed designed it, and Dutch developer Codeglue co-developed the 2014 Steam release. It debuted on PlayStation 3 in 2013, reached PC on May 26, 2014, with achievements, leaderboards and trading cards, and arrived on Nintendo Switch in March 2020, where its couch-co-op premise finally feels at home.

The premise fits on a napkin. Every level is split by a horizon line. Above it, gravity pulls down. Below it, the world is mirrored and gravity pulls up. Ibb and obb, two small, nearly featureless creatures, cross between the halves through warp portals. Each crossing flips their orientation and changes how they see the level. Most of the puzzle design follows from that one rule.

The game sits in a small, well-defined niche. It is not a sprawling adventure like It Takes Two or a narrative showcase like A Way Out. Its closest relatives are Portal 2‘s co-op campaign and Snipperclips: tightly scoped, mechanically focused, and built around communication. There are 15 main levels, 8 hidden worlds, and optional crystals to collect. That is a weekend’s worth of content, not a month’s.

Critics have treated it kindly — it holds an 83 on Metacritic — which is a solid result for a game whose central demand is that you bring a friend. The recurring criticisms are consistent: it is short, it is awkward solo, and its late-game timing can wear down a casual partner. All three are fair. None of them sinks it.

• Dual-Gravity Horizon: Every level is mirrored across a horizon line with opposite gravity. Portals let players flip between the two halves, and each move turns traversal into spatial reasoning.
• Mandatory Interdependence: One player stands on the other to reach a ledge, launches a partner through a portal, or draws an enemy away while the other gets into position. Solo play is technically possible, but the design never assumes it.
• Cross-Horizon Combat: Enemies can only be killed by jumping through their weak spot from the opposite side of the horizon. Even combat becomes a coordination puzzle.
• Local and Online Co-op: Couch co-op is the main event. Online play with a friend or a random partner is supported, though the pool of random partners is thin for a game this age.
• Hidden Worlds and Crystals: Eight secret worlds and collectible crystals add a layer of completionist replay for pairs who want more.
• Kettel Soundtrack: Dutch electronic artist Kettel provides a warm, ambient score that keeps the mood calm even when the puzzles aren’t.

The Gravity Loop

The dual-gravity mechanic works because it is legible. Within seconds it is clear that the bottom half of the screen is an upside-down mirror of the top. Within minutes it becomes a second world with its own physics, not a copy. A jump that falls short above the line becomes a launch below it, because momentum carries through the portal and gravity reverses on the other side. Sparpweed uses this well. Early levels teach the basic crossing. Middle levels ask for chained crossings, using one side’s fall to build speed for the other side’s rise.

The design is disciplined. Ibb & Obb rarely adds new systems. It gets new puzzles out of the same few rules, which is the hardest and most respectable way to design a puzzle game. When a level surprises, it’s because there is something new to see in a mechanic already understood, not because a new gadget appeared.

Communication as a Mechanic

The game’s real engine is conversation. Ibb and obb are functionally identical: no special abilities, no asymmetric roles. So the game can’t tell either player what to do. The players have to work it out between them. “Stand there.” “No, on my head.” “Wait, go through on three.” That chatter isn’t a side effect. It is the gameplay.

This is also where the game reveals the most about the people playing it. With a patient partner, Ibb & Obb produces some of the better moments in co-op gaming: two people solving a problem that neither could see alone. With a mismatched pair, where one player is a seasoned platformer fan and the other isn’t, it can turn into a strain on the relationship. The game has no rubber-banding and no hint system, and it doesn’t soften failure. Death is instant, and the retry is quick, but the retry doesn’t help if one player keeps missing the same jump.

Difficulty Curve and Pacing

The first two-thirds of the game are close to ideal. Puzzles build in complexity at a steady rate, and checkpoints are generous. The final levels are where the complaints begin. Late-game challenges move from reasoning to execution: frame-sensitive jumps, synchronised portal crossings, and enemy patterns that demand precise timing from both players at once. That is a legitimate design goal, but it changes the game’s contract. Players stop solving puzzles together and start performing them together. That is a different skill, and casual players may not have signed up for it.

The short runtime is the other sticking point. Fifteen levels plus hidden worlds will take most pairs somewhere in the range of a few evenings. The brevity reads as a feature, since the core idea is fully explored and nothing overstays its welcome. Still, anyone expecting a long campaign will feel shortchanged.

Solo Play: Don’t

The game allows one player to control both characters, one per analog stick. This is a technical allowance, not a real mode. Controlling two bodies that need precise synchronisation with two thumbs is awkward at best and miserable at worst. The puzzles also lose their point, because the conversation that drives them has nobody on the other end. With nobody to play with, buy something else.

Online Play

Online co-op with friends works as advertised, and it makes the game viable for long-distance pairs. Random matchmaking is a different story. The game is more than a decade old, and its community has long since moved on, so the queues are very quiet. Treat online play as a friends-only feature.

Ibb & Obb’s art direction is soft, minimalist, and pastel: geometric shapes, gentle gradients, and characters reduced to a few simple forms. The restraint serves a purpose. With the screen split in two and gravity flipped on one half, visual noise would be disastrous. Here the silhouettes of platforms, portals and enemies read instantly on both sides of the horizon, and colour shifts signal which half is which. It is readable design wearing a pleasant art style.

Kettel’s soundtrack does a lot of emotional work. Its ambient electronic textures lower the stakes during the frustrating late-game retries, and the game is better for it. It is the kind of score noticed most when it stops.

Performance should not be a concern on paper. This is a lightweight 2D game of a scope that is light on hardware, well within reach of low-end laptops and the Switch alike. The UI is sparse, perhaps too sparse: there’s little in-game guidance beyond the level itself, which suits the puzzle ethos but raises the onboarding friction for new players.

Steam: The PC version is the definitive feature set, with achievements, leaderboards, and trading cards on top of the core game. Gamepads are the way to play. Keyboard play for two people on one keyboard works in theory but gets cramped and imprecise quickly, especially in the timing-heavy late levels. Remote Play Together makes the Steam version an option for pairs who don’t share a room, sidestepping the thin online matchmaking.

Nintendo Switch: The 2020 Switch release is where Ibb & Obb makes the most sense. Two Joy-Cons, one each, and there is a complete co-op setup anywhere: on the sofa, on a train, on a tabletop in handheld stand mode. A single Joy-Con may feel cramped for the tighter late-game jumps, so a Pro Controller or a second pair of full controllers helps. The friction of starting a couch co-op session is close to zero here, and that matters for a game built entirely around sitting next to somebody.

Ibb & Obb is a well-built game that knows exactly what it is. Sparpweed took one elegant idea, a world mirrored across a horizon with gravity pulling both ways, and built a short campaign where every level depends on two people talking to each other. The pastel minimalism and Kettel’s score make it inviting. The puzzles make it smart. The interdependence makes it memorable.

The flaws are real. The late game trades cleverness for execution, the campaign ends early, and solo play is a non-starter. But these are the costs of a game that refuses to compromise its premise, and that conviction is easier to admire than to fault. We recommend it to pairs with one reliable co-op partner and the patience for its final stretch. Without a partner, it has nothing to offer.