Metal Slug 4 (2002). Play online

Summary

Metal Slug 4 drops you back into the frantic run‑and‑gun action of the Neo‑Geo arcade cabinets, this time chasing a lethal cyber virus that’s hijacking military computers. Marco and Fio team up with fresh faces—Nadia Cassel, a tech‑savvy specialist, and Trevor Spacey, a hulking powerhouse—to trace the attack to the shadowy Amadeus terror group. The game keeps the familiar slab‑throwing chaos but adds a “Metallix” combo system that tallies kills within a tight time window, rewarding speed‑run perfection with extra points and badges.

New vehicles pop up throughout the levels, alongside expanded weapon types, letting you blast through the virus‑infested battalions with fresh firepower. The bonus scoring mechanic urges rapid enemy shredding, turning each stage into a frantic high‑score race while the story of digital warfare unfolds in the background.

Storyline

One year after the events of Metal Slug 3, the world is trembling under a new threat: a mysterious cyber virus capable of destroying any nation’s military computer system. This danger sets the stage for Metal Slug 4’s arcade storyline.

With Tarma Roving and Eri Kasamoto tied up on other assignments, veteran soldiers Marco Rossi and Fiolina "Fio" Germi are summoned. They are soon joined by two newcomers, Nadia Cassel and Trevor Spacey, forming a fresh four‑person squad.

The team uncovers that the Amadeus Syndicate—a wealthy terrorist organization linked to General Morden’s Rebel Army—is behind the virus plot. Their mission becomes a race to stop Amadeus forces and prevent the cyber weapon from wiping out global military networks.

Mid‑game the squad confronts a presumed Morden, only to discover an underground lab producing android replicas of the general. The final showdown pits the heroes against the syndicate’s leader, known only as “Doctor,” who attacks with powerful robots. After defeating him, the base self‑destructs; players can escape to see the cast celebrate, or be caught in the blast and appear bandaged in a hospital, with a mysterious data transmission flashing on a monitor before shutting down.