Telesto is a modern multi-system libretro emulator frontend for Windows, inspired originally by OpenEmu on macOS.
Named after the planet Saturn's real moon and also the name I have affecionately given the character from the iconic Sega Saturn commercials, Telesto itself orbits around interesting projects in 2026 emulation while using Emutastic as home planet.
Telesto provides a sleek, unified interface for all your retro gaming needs under one easy to understand house. Built for people just want to pick up and start gaming easily.
Telesto would not exist without the strong work of Emustastic bringing OpenEmu over to Windows.
-
34+ emulated systems across 11 manufacturers with automatic core selection.
-
Integrated Sega Saturn emulation from fork via the Ymir core (embedded or standalone). We want to bring more eyes to the ymir project.
- Windows 10/11 (x64)
- .NET 8 Desktop Runtime - Download here
- Visual C++ Redistributable 2015–2022 (x64) - Download here
- libretro core
.dllfiles (downloadable in-app) SDL3.dll(x64) for controller name detection (downloadable in-app)ffmpeg.exefor video recording (downloadable in-app)- DAT files for ROM identification (downloadable in-app)
Windows SmartScreen: Telesto is not code-signed. Click "More info" then "Run anyway" on first launch.
Telesto supports 34 systems across 11 manufacturers with automatic core selection and intelligent fallback.
| System | Tag | Core (priority order) | BIOS Required |
|---|---|---|---|
| NES | NES | nestopia → quicknes → fceumm | No |
| Famicom Disk System | FDS | nestopia | disksys.rom |
| SNES | SNES | snes9x → bsnes | No |
| Nintendo 64 | N64 | parallel_n64 → mupen64plus_next | No |
| GameCube | GameCube | dolphin | No |
| Game Boy | GB | mgba → gambatte → sameboy | No |
| Game Boy Color | GBC | mgba → gambatte → sameboy | No |
| Game Boy Advance | GBA | mgba | Optional |
| Nintendo 3DS | 3DS | azahar | No |
| Nintendo DS | NDS | desmume → melonds | No |
| Virtual Boy | VirtualBoy | mednafen_vb | No |
| Genesis / Mega Drive | Genesis | genesis_plus_gx → picodrive | No |
| Sega CD / Mega CD | SegaCD | genesis_plus_gx | Region BIOS |
| Sega 32X | Sega32X | picodrive | No |
| Sega Saturn | Saturn | ymir (embedded) → ymir (standalone) → mednafen_saturn → kronos → yabause | Region BIOS |
| Master System | SMS | genesis_plus_gx → picodrive | No |
| Game Gear | GameGear | genesis_plus_gx | No |
| SG-1000 | SG1000 | genesis_plus_gx | No |
| Dreamcast | Dreamcast | flycast | No |
| PlayStation | PS1 | mednafen_psx_hw → mednafen_psx | Region BIOS |
| PSP | PSP | ppsspp | No |
| TurboGrafx-16 | TG16 | mednafen_pce → mednafen_pce_fast | No |
| TurboGrafx-CD | TGCD | mednafen_pce → mednafen_pce_fast | syscard3.pce |
| Neo Geo Pocket | NGP | mednafen_ngp | No |
| Neo Geo Pocket Color | NGPC | mednafen_ngp | No |
| Neo Geo | NeoGeo | geolith | neogeo.zip + aes.zip |
| Arcade | Arcade | fbneo | No |
| Atari 2600 | Atari2600 | stella | No |
| Atari 7800 | Atari7800 | prosystem | No |
| Atari Jaguar | Jaguar | virtualjaguar | No |
| ColecoVision | ColecoVision | gearcoleco → bluemsx | No |
| Vectrex | Vectrex | vecx | No |
| 3DO | 3DO | opera | panafz10.bin |
| Philips CD-i | CDi | same_cdi | No |
Place BIOS files in %AppData%\Telesto\System\ (or PortableData\System\ next to the .exe in portable mode). The app also checks each system's ROM folder.
Sega CD — bios_CD_U.bin (USA), bios_CD_E.bin (Europe), bios_CD_J.bin (Japan)
Sega Saturn — Ymir automatically detects and copies your Saturn IPL BIOS files (sega_101.bin, mpr-17933.bin, mpr-17941.bin) from Telesto's central System directory directly into the emulator profile's roms/ipl subdirectory on launch.
PlayStation — USA: scph5501.bin, scph1001.bin, scph7001.bin. Europe: scph5502.bin. Japan: scph5500.bin
TurboGrafx-CD — Any of: syscard3.pce, syscard2.pce, syscard1.pce
3DO — Any of: panafz10.bin (Panasonic), panafz1j.bin (Japan), goldstar.bin (GoldStar)
Famicom Disk System — disksys.rom
Telesto makes importing your ROM collection simple and intelligent:
- Drag & drop ROMs directly onto the library
- Automatic detection via file extension and SHA1 lookup against DAT files
- Smart multi-disc bundling (Final Fantasy VII, Metal Gear Solid, etc.) automatically creates single library entries
- Hand-authored
.m3uplaylists are honored as-is - Ambiguous formats (
.chd,.iso,.cue,.bin) show a console picker if no DAT match is found
Important: Download DAT files in Preferences → Cores / Extras before importing for best results.
Telesto features deep integration with the Ymir Saturn emulator core:
- Direct Rendering: Software-rendered frames captured via native callbacks
- Integrated Audio: Stereo sample callbacks stream directly into Telesto's audio player
- Unified Controls: Native button mapping to Ymir's Saturn digital pad button masks
- Saves & Backups: Automatic creation and formatting of backup RAM
- No Open Trays: Automatically handles virtual disc tray after boot
- Profile Seeding: Clean local Ymir profile with updates disabled
- BIOS Synchronization: Automatic copying of IPL BIOS files to standalone profile
- Four built-in themes: Dark (default), Light, OLED Black, Midnight Blue
- Full visual editor with 44 color tokens and live preview
- Custom background images with zoom, pan, and tile controls
- Export/import themes as
.emuthemefiles
- XInput button polling during gameplay
- SDL3 device name detection for hundreds of controllers
- Per-controller button mapping in Preferences → Input
- Falls back to generic names if
SDL3.dllis absent
- Earn achievements while playing via RetroAchievements
- Enable in Preferences → Achievements with your RA username and password
- Achievements appear as toast notifications during gameplay
- Preferences → About shows version, build date, and credits
- Automatic GitHub release checking with manual download option
- Notification-only — no auto-installer, no telemetry
- Per-core settings (internal resolution, graphics plugins, etc.)
- Access in Preferences → Core Options
- Press L3 + Start in-game to flip between discs/sides
- Rebindable to any two-button chord in Preferences → Controls → Disk Swap
- Status bar shows new disc number on each swap
- Multi-disc games auto-bundled at import time
Telesto.exe / rcheevos.dll / .NET runtime DLLs
%AppData%\Telesto\ (or your custom data folder)
library.db
Native\ (SDL3.dll, ffmpeg.exe)
DATs\ (No-Intro / Redump DATs)
Cores\ (libretro core DLLs)
System\ (BIOS files)
Save States\ / BatterySaves\ / Screenshots\ / Recordings\ / Artwork\ / ...
Drag and drop ROMs onto the library or use Import ROMs. The app detects the console from file extension, cleans the title, and hashes the ROM. For ambiguous formats (.chd, .iso, .cue, .bin), a SHA1 lookup against DAT files is attempted first — if no match, a console picker is shown.
Multi-disc games (Final Fantasy VII, Metal Gear Solid, etc.) are auto-bundled into a single library entry — drop a folder containing the disc files (.cue/.bin or .chd) and Telesto writes an .m3u playlist alongside them so the game shows up once, not three times. Hand-authored .m3u files in the folder are honored as-is.
Important: Download DAT files in Preferences → Cores / Extras before importing. Without them, disc images and some cartridge ROMs may be assigned to the wrong system during import.
Telesto supports Sega Saturn emulation through the Ymir core (developed by StrikerX3). We offer two integration paths:
Telesto hosts the Ymir emulator in-process via a native C++ wrapper (telesto-ymir-core.dll) and a managed P/Invoke layer (YmirNativeCore).
- Direct Rendering: Software-rendered XRGB8888 frames are captured via native callbacks and presented directly onto Telesto's
WriteableBitmaprendering surface. - Integrated Audio: Stereo sample callbacks stream audio directly into Telesto's
AudioPlayerqueue. - Unified Controls: Native button mapping maps Telesto's user-configured input profiles directly to Ymir's internal Saturn digital pad button masks.
- Saves & Backups: Automatic creation, formatting, and seeding of internal backup RAM as well as a 32 Mbit backup RAM cartridge image.
- No Open Trays: Automatically handles closing the virtual disc tray after boot to bypass standard CD player BIOS screens.
Launches the standalone ymir-sdl3.exe external emulator while keeping it aligned with Telesto.
- Profile Seeding: Telesto automatically provisions and maintains a clean local Ymir profile directory under
YmirProfiles/default, disabling automated update checks and enabling per-game internal backup RAM. - BIOS Synchronization: On launch, Telesto checks for your Saturn IPL BIOS files (
sega_101.bin,mpr-17933.bin,mpr-17941.bin) in your centralSystemdirectory and copies them directly into the standalone profile'sroms/iplsubdirectory.
Themes
Four built-in themes: Dark (default), Light, OLED Black, Midnight Blue. Full visual editor with 44 color tokens and live preview. Set custom background images with zoom, pan, and tile controls. Export/import themes as .emutheme files.
Controllers
XInput button polling during gameplay with SDL3 device name detection. Xbox, DualSense/DualShock, and hundreds of other controllers are identified by product name. Button mappings configurable per-controller in Preferences → Input. Falls back to generic names if SDL3.dll is absent.
RetroAchievements
Earn achievements while playing via RetroAchievements. Enable in Preferences → Achievements with your RA username and password. Achievements appear as toast notifications during gameplay.
About & Updates
Preferences → About shows the current version, build date, and credits. On open, it checks GitHub for the latest release and surfaces a download link if a newer version is available. Notification-only — no auto-installer, no telemetry.
- Core Options — Per-core settings (internal resolution, graphics plugins, etc.) in Preferences → Core Options
Disk Swapping (FDS, PS1, Saturn, Sega CD)
Press L3 + Start in-game to flip between discs/sides on systems that need it. Rebindable to any two-button chord (controller or keyboard) in Preferences → Controls → Disk Swap. The status bar shows the new disc number on each swap.
Multi-disc games are auto-bundled at import time — see the ROM Import section. See the wiki page for per-console specifics and troubleshooting.
Telesto.exe / rcheevos.dll / .NET runtime DLLs
%AppData%\Telesto\ (or your custom data folder)
library.db
Native\ (SDL3.dll, ffmpeg.exe — downloadable in-app)
DATs\ (No-Intro / Redump DATs — downloadable in-app)
Cores\ (libretro core DLLs — downloadable in-app)
System\ (BIOS files)
Save States\ / BatterySaves\ / Screenshots\ / Recordings\ / Artwork\ / ...
Drop an empty portable.txt next to Telesto.exe or launch with the --portable command-line flag, and everything lives in PortableData\ beside the .exe — config, library database, save states, battery saves, screenshots, recordings, artwork, BIOS files, libretro cores, and any ROMs you import. Move the install folder to a USB stick and run it on any Windows PC; library paths are stored relative to PortableData\ so drive-letter changes (E:→F:) don't break anything. ROM imports are auto-copied into PortableData\Roms\<Console>\ so they travel with the USB without setting up a separate library folder. See Portable Mode in the wiki for the full on-disk layout, caveats, and how to revert.
Requires Visual Studio 2022+ with .NET desktop development workload.
git clone <repo>
cd Emutastic
dotnet build .\Emutastic.sln -c Release
Credits
Emulation is handled by libretro cores maintained by their upstream authors. Telesto bundles none of them — the in-app core manager downloads from the libretro build servers on demand. Please support these projects directly.
| Core | Upstream author(s) |
|---|---|
| Azahar | Azahar team (successor to Citra / Lime3DS) |
| Beetle PSX / Saturn / PCE / VB / NGP | Mednafen team (Ryphecha) |
| blueMSX | blueMSX team (Daniel Vik and contributors) |
| bsnes | byuu / near and contributors |
| DeSmuME | DeSmuME team |
| Dolphin | Dolphin team |
| FBNeo (FinalBurn Neo) | FBNeo team |
| FCEUmm | FCEUmm team |
| Flycast | flyinghead and contributors |
| Gambatte | Sindre Aamås (sinamas) |
| Gearcoleco | Ignacio Sánchez (drhelius) |
| Genesis Plus GX | Eke-Eke |
| Geolith | R. Danbrook (rdanbrook) |
| Kronos | Kronos team |
| melonDS | Arisotura |
| mGBA | Vicki Pfau (endrift) |
| Mupen64Plus-Next | libretro team |
| Nestopia UE | Nestopia UE team |
| Opera | libretro team (3DO) |
| ParaLLEl-N64 | libretro team (Themaister and contributors) |
| Picodrive | notaz |
| PPSSPP | Henrik Rydgård and contributors |
| ProSystem | Greg Stanton (upstream) / libretro maintenance |
| QuickNES | Shay Green (blargg) |
| SAME CDi | CDi community (MAME derivative) |
| Snes9x | Snes9x team |
| Stella | Stella team |
| VecX | Valavan Manohararajah (upstream) / libretro maintenance |
| Virtual Jaguar | Virtual Jaguar team |
| Yabause | Yabause team |
| Ymir | StrikerX3 (high-accuracy Sega Saturn emulation core) |
Artwork from OpenEmuControllerArt (BSD 3-Clause). Not affiliated with or endorsed by OpenEmu.
| Artist | Controllers |
|---|---|
| David McLeod (@Mucx) | 32X, FDS, GB, GBA, Game Gear, SMS, NES, Sega CD, Genesis, SNES |
| Ricky Romero (@RickyRomero) | Atari 2600/5200, N64, NDS, Odyssey², PS1, PSP, Saturn, SG-1000, Vectrex, Virtual Boy |
| Craig Erskine (@qrayg) | GameCube, Neo Geo Pocket, PC Engine / TG16 |
| Salvo Zummo / David Everly / Kate Schroeder | Atari 7800, 3DO, ColecoVision |
Inspired by OpenEmu for macOS.