Leviathan - EVO3 is an advanced microprocessor-controlled MOSFET unit programmable via Bluetooth. The EVO3 designation means this unit is compatible with ASG CZ Scorpion EVO 3 airsoft guns. Leviathan brings a wide range of new features to the EVO3 AEG and improves existing functions. With this unit, you can control your gun’s fire modes, rate of fire (ROF), pre-cocking, active braking, protect LiPo/LiFe batteries from over-discharge, and much more. All features are managed via a smartphone app (Android and iOS). The Leviathan unit is installed inside the EVO3 gearbox, replacing the traditional trigger contacts. It comes with pre-installed wiring, including a 30A mini fuse and Deans/T-connectors. No soldering required during installation!
Note! The gearbox and trigger shown in the picture are not included with the unit.
What features does the Leviathan unit provide?
- Adjust and add all fire modes in any selector position (SAFE - SEMI - AUTO).
- Three different burst fire modes. Each burst length adjustable between 2 - 20 shots.
- Limit the gun’s rate of fire by adding motor pauses between shots. This keeps trigger response extremely fast while reducing full-auto speed electronically.
- Adjustable active brake strength, which can also be disabled.
- "Pre-cocking" function for instant semi-auto response without delay.
- ARL mode: Included anti-reverse latch allows pre-cocking, lower-level active braking, and use of DSG gears.
- Option to add a delay between shots to simulate the effect of recoil on shooting speed. Delay adjustable between 0.1 - 4 seconds.
- Automatic fuse detects high current to prevent damage if something goes wrong.
- Low voltage warning for LiPo or LiFe batteries. Works with 2S - 4S LiPo and 3S - 4S LiFe batteries.
- User can save multiple configuration profiles.
- Software displays real battery voltage with a color-coded indicator for charge level.
- Three separate shot counters: total lifetime shots, user-resettable counter, and one that resets when the battery is disconnected.
- Error log records all errors during the unit’s lifetime.
- Leviathan - EVO3 monitors current, voltage, and temperature, protecting components from damage in case of failure.
- Motor vibrates and beeps to provide feedback to the user.
- Settings are saved in real time to Leviathan - EVO3 memory, so you won’t lose them if Bluetooth disconnects or the battery is removed during adjustment.
Programmable fire modes:
Each mode below can be assigned to any selector position (SAFE - SEMI - AUTO).
- SAFE: Trigger pull does nothing, gun is on safe.
- SEMI: Fires one shot per trigger pull.
- SEMI/BurstX: Short pull fires one shot, long pull fires a preset burst.
- "Double trigger": Fires once on pull and once on release (two shots per full trigger cycle).
- BurstX: Fires a burst with one trigger pull.
- BurstX/BurstY: Short pull fires burstX, long pull fires burstX followed by burstY.
- BurstX/Full: Short pull fires burstX, long pull fires full-auto.
- Full: Fires full-auto as long as the trigger is held.
Specifications:
- Easy to install in ASG CZ Scorpion EVO 3 AEG, no modification to the gun or circuit required.
- Compatible with Scorpion EVO 3 - A1, Scorpion EVO 3 - A1 B.E.T., Scorpion EVO 3 - A1 carbine gearbox gen.1, 2018 version, and 2020 version. Works with standard or CNC trigger.
- ARL mode: Included anti-reverse latch allows pre-cocking, lower-level active braking, and DSG gear use.
- Sector gear and trigger position monitored by micro switch for perfect semi and burst timing.
- Includes CNC-machined trigger with adjustable pull length via set screw.
- Leviathan unit comes with complete wiring for easy installation. Wires are long enough for all EVO3 gearbox setups with battery in the stock. No soldering required.
- High-quality pre-installed 1.5 mm² (1.5 qmm / AWG16) power wires with durable MPPE insulation and blue 0.34 qmm signal wire (AWG24)
- Power wire outer diameter: 2.06 mm
- Signal wire outer diameter: 1.24 mm
- Wire length from gearbox rear to battery connector: 290 mm
- Electronic board coated with lacquer for water protection.
- Pre-cocking function requires anti-reversal latch to prevent gear backspin.
- Designed to operate with batteries up to 17V. Compatible with 8.4 - 12V NiMH and 7.4 - 14.8V lithium-based batteries.
- Parts removed from gearbox during installation: cut-off lever and stock electrical components.
Links:
JeffTron mobile app for Leviathan on iOS and Android
Leviathan EVO3 manual: Download the installation and user manual HERE
Package Includes:
- Leviathan - EVO3 "drop-in module" with front wiring. Deans/T-connector on wires. Motor wires with standard motor connectors.
- ARL mode: Anti-reverse latch, spring, and special screw
- Two washers for screws
- Foam pad for Leviathan installation
- English installation manual
Safety Instructions:
- Installing the unit inside the gearbox requires knowledge of airsoft gun mechanics.
- Read the manual before installation to avoid damage!
- Short circuit or incorrect battery connection will immediately damage the unit! Incorrect wiring voids warranty and may cause battery explosion!
- Always disconnect the battery when the gun is not in use! Otherwise, the circuit may slowly drain the battery, rendering it unusable. When connected, Leviathan draws a small standby current.
- Always ensure the barrel is pointed in a safe direction before connecting the battery!
- Do not modify, repair, or expose the Leviathan EVO3 board to liquids or heat.
VIDEO: Leviathan - EVO3 Features:

