Joystick Gremlin Guide: Merge HOTAS Devices into One vJoy

If you fly with a stick in one hand, a throttle in the other and pedals under the desk, your simulator sees three separate controllers — and not every game handles that gracefully. Joystick Gremlin solves the problem by taking all of your physical devices and presenting them to the game as a single virtual joystick. That virtual joystick is vJoy, and understanding that relationship is the key to the whole setup: Joystick Gremlin has no driver of its own, its own README states that it requires vJoy underneath, and every axis and button Gremlin produces is written into a vJoy device that the game then reads like ordinary hardware.

This guide covers what Joystick Gremlin does, the install order that makes it work, the core setup steps for merging devices, and the limits you should know about before you build a profile around it.

What Joystick Gremlin does

Joystick Gremlin, by WhiteMagic, is a feeder application: it uses the virtual joysticks provided by vJoy to map physical inputs to virtual ones. Its headline features are merging multiple physical devices into a single virtual device, response curves that reshape how an axis reacts around the centre, modes that let one physical control do different jobs in different phases of flight, macros that turn a button press into a sequence of actions, and Python scripting for setups the built-in actions cannot express.

The merging is the part most people come for. A vJoy device offers up to 8 axes, up to 128 buttons and up to 4 POV hat switches, so a stick, throttle quadrant and a set of rudder pedals can be combined into one device with room to spare. Instead of the game juggling three controllers — and occasionally reordering them after a reboot — it sees one stable vJoy device whose layout you designed. Response curves then fine-tune the result: a gentle curve around the centre makes small corrections in a dogfight or on final approach much easier, while the outer range still reaches full deflection.

Install order: vJoy first, Gremlin second

The order matters because Gremlin writes to vJoy devices that must already exist. Installing Gremlin first leaves it with nothing to feed, which is the most common reason a fresh setup appears to do nothing at all.

1. Install vJoy from our download page. On Windows 10 and 11 the current signed build is 2.2.2.0; keep 2.1.9.1 in mind as the compatibility fallback described below.
2. Open vJoyConf (Configure vJoy) and configure the vJoy device Gremlin will feed — typically device 1 — with at least as many axes and buttons as your merged layout needs.
3. Restart if the installer asks, then confirm the vJoy device exists in Windows before going further. Our vJoy setup hub walks through this stage in detail.
4. Install Joystick Gremlin and start it. It should detect the vJoy device you configured; if it cannot find one, the vJoy step above is where the problem lives, not Gremlin.
5. Leave Gremlin running whenever you play. The virtual device only receives your merged inputs while the feeder is active.

Core setup steps

With both programs installed, building a working profile follows a predictable sequence:

1. Create a new Gremlin profile for your game. Everything you map — axes, buttons, curves, modes and macros — is stored in this profile, so one profile per game is the normal pattern.
2. Add your physical devices and map each stick, throttle and pedal axis onto the matching axis of the vJoy device. This axis merging step is where two sticks become one virtual controller.
3. Map physical buttons to virtual buttons. Because the vJoy device can expose up to 128 buttons, merged setups rarely run out.
4. Add a response curve to the axes that need one — pitch and roll first — and test how the curve feels before copying it everywhere.
5. If you need them, define modes (for example one mode for takeoff and landing, another for combat) and macros for repeated sequences, then set how you switch modes from the hardware itself.
6. Activate the profile, open the vJoy monitor or the Windows game controller panel, and move every control end to end. Each physical input should move exactly one virtual axis or button, with nothing doubled and nothing dead.

A note on profiles: a Gremlin profile is only a file of instructions until it is loaded and active. If a game suddenly ignores your curves or merged axes, check first that Gremlin is running and that the correct profile for that game is the active one. Keeping a backup copy of a finished profile is worth the few seconds it takes — rebuilding modes and macros from memory is nobody’s idea of fun.

Best use case

Gremlin earns its place in flight and space sims where pilots combine several controllers. It is part of the documented Star Citizen community stack — vJoy plus Joystick Gremlin plus HidHide — where dual-stick HOSAS rigs are merged into virtual devices the game can bind cleanly, and the same pattern is widely used in DCS to fold a stick, throttle and pedals into one device. Our games and sims hub collects the per-game guides that build on this setup. If you own one simple stick and one game that already handles it well, Gremlin adds little; its value scales with the amount of hardware you are merging.

Limitations

• Gremlin cannot work alone. It has no driver of its own and requires vJoy underneath — if vJoy is broken, Gremlin output goes nowhere.
• DirectInput only. vJoy is a DirectInput device and does not emulate XInput. A game that only accepts Xbox controllers needs an extra layer (the feeder → vJoy → x360ce chain) or a different tool.
• Feeder compatibility varies by vJoy build. Some feeders only partially support the 2.2.x line. If Gremlin misbehaves on 2.2.2.0, installing 2.1.9.1 is the honest compatibility fallback — test your feeder against your build.
• Depth takes time. Modes, macros and scripting are powerful, but a full profile is an evening of mapping and testing, not a five-minute job.

Next steps: get the driver from the download page, browse the other feeders in the vJoy feeder tools hub, and if your game still sees your physical sticks alongside the merged one, read our HidHide guide — it is the sibling tool that hides the physical devices so only the virtual one reaches the game.