Before You Start

Add a Nintendo DS game to your Rebit library and sign in on each device.
For normal local wireless, both players need the exact matching ROM, including region and revision.
Save inside the game and export your in-game save before creating or joining a room.
Keep both devices awake with the game visible.
Check that the game supports the multiplayer feature you want to use.

Choose a Nintendo DS Mode

Mode	Use it for
Lockstep	Two-player local wireless with synchronized gameplay. Start here.
Rollback	Local wireless with input prediction and correction on supported devices. It can require more from the browser or device.
Download Play	Supported games that let a host supply the game to a guest through the DS Download Play feature.

A disabled mode shows why it cannot run in the current browser or app. Try an updated browser if your device cannot use it.

Host a Nintendo DS Room

Open your Nintendo DS game and select Play Now.
Open the in-game menu and select Netplay.
Choose Lockstep, Rollback, or Download Play.
Select Start Host.
Copy the Room ID and ask the other player to find it in Netplay.

Nintendo DS Local Wireless currently uses two players. The old Cloud guide's 3P and 4P instructions do not apply to these rooms.

Join by Room ID

Open Netplay and find the host's Room ID.
Select Join.
Choose the eligible game from your library.
Wait for the room to connect.

Lockstep and Rollback require the exact matching Nintendo DS ROM. For Download Play, the host supplies the cartridge; the guest still chooses an NDS library entry to open the session, but that entry does not need to match the host's game.

Join from Netplay or Discover

Use Join on the room entry in Netplay, or an active-room entry shown in Discover. Rebit uses the room's mode automatically and shows the appropriate game selection prompt.

Start Playing Together

Connecting the Rebit room prepares the consoles; you still need to use the game's own local wireless menu. Follow the game's instructions for hosting and joining a battle, race, trade, or other multiplayer activity.

For Download Play, use a game that supports it and follow the host game's Download Play flow. It is different from joining with two copies of the cartridge.

Keep Your Save

Save inside the game, then select Export In-Game Save when available and wait for confirmation. Use the normal Leave action so Rebit can finish saving and disconnecting; avoid closing the tab while it says it is saving.

A Download Play guest does not have an ordinary cartridge save for the host's game. Save-state loading and other solo actions may be unavailable during wireless play.

Nintendo DS Cloud Rooms

Cloud hosting is currently disabled and shows NDS Cloud is offline. Use an available Local Wireless mode instead. Cloud capacity, region selection, and old cloud-stream instructions do not apply to Local Wireless.

Leave a Room

Tell the other player before leaving, especially during a trade or save. Open Netplay and use the active session's Leave action. If a game cannot recover after someone disconnects, create a fresh room.

Nintendo DS Multiplayer Troubleshooting

No matching ROM: check the game's region and revision on both accounts.
Players cannot find each other in-game: confirm the game supports the selected local wireless or Download Play feature.
The room is waiting or paused: keep both pages visible and check the other player's connection.
Rollback is unavailable: read the device requirement shown in the menu and try Lockstep if offered.
A save is missing: check the game's In-game saves and export before leaving next time.

Nintendo DS multiplayer does not currently produce the replay captures described in Watch and Multiplayer Replays.