Can You Play DS Multiplayer Games on a Nintendo 3DS? Not Locally—Here's Why and Workarounds
No, not directly via local wireless (Download Play / Local Play).
Why It Fails
Different wireless protocol: DS games use a proprietary "NiFi" local wireless protocol. The 3DS has a separate Wi-Fi radio for its own local play; it does not emulate NiFi for DS software.
Missing hardware link port: The 3DS lacks the physical "Game Link Cable" port (used by GBA/DS for some titles), though this is rarely the primary multiplayer method.
System mode: When a DS game runs on 3DS, the system enters "TWL_FIRM" mode, which sandboxes the DS hardware. The 3DS's extra CPU/RAM and its own Wi-Fi are inaccessible to the DS game.
Workarounds
Two 3DS systems + DSiWare versions: If the game was released as DSiWare (e.g., Four Swords Anniversary Edition, some Pokémon distribution tools), two 3DS systems can link via 3DS local wireless.
Online via custom servers (Wiimmfi / AltWFC): Both players use a 3DS (or DS) connected to Wiimmfi. The game thinks it's online (WFC), not local. Works for Mario Kart DS, Pokémon Gen 4/5, Animal Crossing: Wild World, etc.
Emulation (melonDS / DeSmuME / RetroArch): On PC/Android, these emulators support netplay for local multiplayer games over LAN/Internet. Requires owning the game dump legally.
Bottom line: For original DS cartridges, you need two original DS/DSi/DSi XL systems for local wireless. A 3DS cannot join that session.
