Flipping is Hard online co-op

Online co-op supports up to 16 players in Steam Friends lobbies that are private, friends-only, or invite-only. The Help Beam can pull a fallen friend upward, and the player using it bounces while that happens. The Steam page also lists microwaves as a way to help. Proximity chat gets clearer when players are closer. Each player needs a copy of the game. The button for the beam is not published in the sources used here.

Who can join

The studio says co-op runs through Steam Friends lobbies, and that those lobbies are private, friends-only, or invite-only, with Steam authentication. The point, in the studio's words, is that an uninvited viewer cannot drop into a session. The creator notes add that every player needs their own copy. The store lists the game as single-player and online co-op, and it flags in-game chat and online interactivity.

Sixteen is the cap on both the store page and the studio site. A DualShockers review lists the same 1 to 16 range and says its writer had not been in a multiplayer lobby. The tool descriptions below come from the studio and the store.

Three brick phones with player name labels perched on a narrow metal structure above a long drop.
Steam store screenshot. Several phones share one narrow structure, with name labels over them. The names in the shot are session labels, not a cast list.

The Help Beam pulls, and it throws you around

Steam's co-op bullet is "use beams and microwaves to help your friends." The studio is more specific about the beam. It pulls fallen friends up toward you. While it does that, you bounce around uncontrollably. The studio calls the result risky. A creator note makes the same point in fewer words: using the beam to save someone sends you bouncing.

A DualShockers review says the bring-up tool shows up early and cannot be used when you are alone. That matches a tool whose whole job is other players. The world page also introduces Beamer, a Playground character who is stuck in the Help Beam pose. That is a character, not the button.

Several phones on a wooden tower, with a bright spiral beam around the blue phone in the center.
Steam store screenshot of a spiral beam on a wooden tower, with more than one phone in the frame.
A large colorful cannon launches several phones while another phone waits on the blocks below.
Steam store screenshot. Several phones are in the air around a cannon. The press kit lists cannons as a climb hazard. It does not say the cannon is a co-op-only object.

Microwaves, as three sources describe them

Three published descriptions sit next to each other, and this page does not mash them into one invented control.

No source used here prints the input for the beam or the microwave. A button guess would be a made-up control. It is left blank on purpose.

Proximity chat

The store says you can yell at your friends as everything goes wrong. The studio says the voice is proximity chat: the closer you are, the clearer it is. The creator notes say a group that is already talking in Discord can mute the in-game voice. This page does not link out to Discord. The mute option is the fact. The store's feature list also includes custom volume controls, which is a separate accessibility tag and not a promise about a specific slider.

What changes when you are alone

The studio calls solo the purest test and co-op the version that turns the same climb into comedy. The checkpoint choice is independent of that. Chill and Hard are described on the movement page and the tips page. Friends do not add a third difficulty name. They add the beam, the microwave help, and the voice.

A DualShockers review argues the game is built with groups in mind, because some help tools do nothing if nobody else is there. That is the review's judgment. The studio still ships a solo option and describes it as the stricter reading of the climb. Both statements can sit together: solo is supported, and several tools exist only when someone else is in the lobby.

Store screenshots of co-op show name labels over the phones. Those labels are players in the shot. They are not added to the cast list, which is limited to characters the world page names.

Practical limits that are actually printed