Similarities between Metal Gear 2: Solid Snake and Metal Gear Solid

Similarities Between Metal Gear 2: Solid Snake and Metal Gear Solid
Many of the gameplay innovations commonly attributed to Metal Gear Solid were in fact introduced eight years earlier by its direct predecessor Metal Gear 2: Solid Snake, which was never released outside of Japan until it was packaged with Metal Gear Solid 3: Subsistence in 2006. As such, Retro Gamer regards Metal Gear 2 to be "as close as anyone can get to playing Metal Gear Solid in 2D."

Plot elements

 * The game opening with a cliff-side open environment before moving inside to a tank-storage room with an elevator.
 * Roy Campbell serving as the main commanding officer to Solid Snake.
 * Master Miller giving advice on improving one's health and professional life.
 * Saving a hostage who appears on radar. In addition, the first hostage of the game is a disguised member of the terrorist faction.
 * Meeting a disguised female contact in a women's washroom.
 * Snake and his female contact (both with the frequency 140.15) effectively becoming romantically involved (Holly in Metal Gear 2 and Meryl in Metal Gear Solid).
 * Helpful messages from an anonymous source via the radio claiming to be a fan of Snake, who turns out to be Gray Fox in both cases.
 * An ally from the previous game betrays Snake (Dr. Madnar in Metal Gear 2 and Master Miller in Metal Gear Solid - although it should be noted that it wasn't Master Miller, but Liquid Snake impersonating as him).
 * Snake conceals some truth concerning Gray Fox in both games (in Metal Gear 2, Snake conceals from Fox the death of Gustava by his own hands and in Metal Gear Solid, he conceals Fox's final message from Naomi).
 * A disguised female contact sneaks up on Snake (Holly in Metal Gear 2 and Meryl in Metal Gear Solid).
 * The return of a major character from the former game decked out as a ninja (Kyle Schneider in Metal Gear 2 and Gray Fox in Metal Gear Solid).
 * The return of a major character presumed dead in the previous game returns (Kyle Schneider and Big Boss in Metal Gear 2 and Gray Fox in Metal Gear Solid).
 * Most of the bosses that Snake defeats in both games give him a dying speech before passing away.
 * The use of the line "It's not over yet, Snake!" Big Boss said it in Metal Gear 2, and Liquid Snake said it in Metal Gear Solid.

Battles

 * An ambush by four hidden attackers in an elevator.
 * A fight with a soldier wearing stealth camouflage.
 * A chase up a spiral staircase with soldiers in pursuit.
 * A battle with a flying Hind D chopper using stinger missiles.
 * Fighting a piloted Metal Gear (Metal Gear D in Metal Gear 2 and Metal Gear REX in Metal Gear Solid).
 * After destroying the Metal Gear of the game, then having an unarmed hand-to-hand showdown with the pilot (Gray Fox in Metal Gear 2 and Liquid Snake in Metal Gear Solid). Similarily, both fights have Solid Snake being stripped of most of his gear for some reason (in Metal Gear 2, Snake was forced to discard most of his weaponry and equipment due to being immolated by Metal Gear D's explosion, and in Metal Gear Solid, Liquid Snake had stripped Snake of most of his equipment)
 * A one-on-one fight between Solid Snake and Gray Fox in both games.
 * An escape from the enemy base alongside a female accomplice (Holly in Metal Gear 2 and Meryl in Metal Gear Solid) while being chased by a horde of enemy guards.

Misc

 * Having to look at the back of the game package to learn an important radio frequency.
 * Having to change the temperature of an object to turn it into a key.
 * Having to heat up frozen rations before eating them.
 * Both the Hind D and the Metal Gear threat have the same boss BGM.