Metal Slug 2 is a run and gun video game developed by SNK. It was originally released in 1998 for the Neo-Geo MVS arcade platform as the sequel to the 1996 game Metal Slug. The original version of the game had extensive slowdown and performance issues, eventually leading SNK to release a modified version in 1999 titled Metal Slug X: Super Vehicle-001 (メタルスラッグX). It has been ported to the Neo Geo CD, PlayStation, Virtual Console, iOS and Android, and to the Wii, PlayStation Portable and PlayStation 2 (as part of the Metal Slug Anthology). The game added several new features to the gameplay of the original Metal Slug, such as new weapons, vehicles and the ability to transform the character. It received generally positive reviews. Gameplay in Metal Slug 2 is similar to the previous game; the player must shoot constantly at a continual stream of enemies in order to reach the end of each level. At this point, the player confronts a boss, who is usually considerably larger and tougher than regular enemies. On the way through each level, the player can find numerous weapon upgrades and "Metal Slug" tanks. The tank is known as the SV-001 ("SV" stands for Super Vehicle), which increases the player's offense and considerably adds to their defense.