Local & Couch Co-op Multiplayer

The "couch co-op but my friends moved away" stack, plus LAN-only-game tunnels. For self-host streaming generally see Self-host streaming (Sunshine + Moonlight). For paid cloud gaming see Cloud gaming. For PC launchers see PC launchers. For controller mapping (a frequent companion problem) see Controller mapping.

The 2024–26 reality: Steam Remote Play Together is the easy default for any Steam title with local co-op — one host, friends join over Steam, controllers tunnel through. Parsec stays popular for non-Steam titles. Sunshine + Moonlight is the FOSS general-purpose path. Tailscale / ZeroTier / Radmin still keep niche LAN-only games (early-2000s shooters, emulator netplay) alive.

Couch-co-op streaming

• ★ ★ Steam Remote Play Together — free; built into Steam. Host launches a local-co-op game; up to 4 friends join via Steam Friends; their controllers / keyboards stream into the host's session. Both sides only need Steam — friends don't need to own the game. Best for any Steam local-coop / split-screen title (Overcooked, Cuphead, It Takes Two, Castle Crashers).
• ★ Parsec — free + paid; closed; Win/Mac/Linux/Android/iOS/web. The original "share my desktop, friends play" tool. Sub-50ms latency, multi-controller pass-through, multi-arcade communities. Free tier covers casual use; Pro / Warp for premium.
• ★ Sunshine + Moonlight — free OSS; see Self-host streaming. Sunshine on host + Moonlight on each guest works for the same use case with more setup but better quality.
• Rainway — pivoted away from this market; mostly historical now.

LAN tunnels (for old or LAN-only games)

• ★ Tailscale — free + paid; mesh VPN. Each device gets a stable WireGuard IP. Great for emulator netplay (Mario Kart on RetroArch), early-2000s LAN-only shooters (Halo CE, BF1942, UT99), Minecraft LAN. Free tier covers personal use cleanly.
• ZeroTier — free + paid; alternative mesh VPN. More configurable, less polished than Tailscale.
• Radmin VPN — free closed; popular with the GTA SA / Stalker / Minecraft co-op crowd. Hamachi-shape but free.
• Hamachi (LogMeIn) — paid; the original; mostly displaced by free alternatives.
• Open VPN / WireGuard self-host — for the comfortable-with-CLI.
• Headscale / NetBird — free OSS; self-host Tailscale-shape control planes.

Emulator-specific netplay

• ★ RetroArch Netplay — free OSS; built into RetroArch. Lobby + relay servers; works for SNES / Genesis / N64 / GBA etc. Lag-free for 2-player retro on a low-latency link.
• FightCade — free; specifically arcade fighting games. Excellent rollback netcode for ST / KOF / 3rd Strike etc. The fighting community's default for retro arcade online.
• Parsec Arcade / Co-op Discord servers — community organizing layers.

Console couch-coop on PC titles

• Universal Split Screen — free OSS Win; forces multi-window splitscreen on games that don't natively support it. Honest flag: glitchy; per-game tweaks; experimental.
• Nucleus Co-op — free OSS Win; same idea; broader title coverage; community-curated handlers.

Pick this if…

• Steam title with local co-op, friends remote: Steam Remote Play Together.
• Non-Steam game, friends remote: Parsec.
• Self-host, FOSS, max quality: Sunshine + Moonlight.
• LAN-only old game over the internet: Tailscale (default) or Radmin VPN (zero-setup).
• Retro emulator co-op: RetroArch Netplay or FightCade.
• Force split-screen on a game that doesn't support it: Nucleus Co-op (with patience).