The gameplay of
Aliens of Gold is very similar to
Wolfenstein 3D. Playable areas are single-leveled, with orthogonal walls and textured floors and ceilings, and have a wide variety of human, mutant and alien enemies – the latter two are sometimes dormant in canisters and on work tables – and frequent encounters and fights with Dr. Goldfire. Level features include locked doors that can be opened by four colors of access cards – gold, green, yellow and blue – plus red access cards to enter new floors; an auto-mapping system; food dispensers that exchange tokens for healing items; friendly interactive Informants who are distinguishable from the Bio-Techs by what they say and give information, ammunition and tokens; one-way doors; secret rooms accessible through pushable wall blocks; and teleporters that instantly take the player into another location within the level, or, in one instance, to one of the episode's secret levels. Five weapons are available, consisting of a silent pistol with infinite ammo, three hitscan guns and a grenade launcher type gun. In every level the player can boost points for score by destroying all enemies, collecting all points and keeping all Informants alive, which increases the three respective statuses. Total Points is affected by both the enemies destroyed and the treasure collected. The 'all informants alive' bonus can only be obtained if all informants survive after the first two bonuses are obtained. Floor rating is affected by the other three statuses. Mission rating is affected by the overall statuses from floors 1 to 9. Killing Informants decreases both Floor and Mission Rating.
Level structure The game consists of six episodes, each with 11
levels – nine regular and two secret. A main elevator goes through levels 1 through 10 and is the only means of moving between the levels. The goal of each level from 1 through 8 is to secure a red
keycard and use it to unlock the next floor. The elimination of all enemies and the collection of all treasure on the current floor are optional objectives which provide bonuses upon completion. "Plasma alien" enemies, which spawn repeatedly from electrical outlets, do not count towards the kill ratio. Blake Stone can take the elevator back down to previous levels to find missed items or kill any remaining enemies. On level 9 of each episode, defeating a stronger version of Dr. Goldfire forces him to drop a gold keycard. The key is used to unlock the way to the boss, which holds another gold keycard for the level's exit – the episode's end. Each episode features two secret levels. One of them, floor 0, can be accessed through a teleport hidden somewhere within the same episode. The other is floor 10, directly accessible through the main elevator. A red keycard is required to enter, and is usually hidden on floor 9. Secret levels do not have special objectives; their only purpose is to boost the player's score. ==Development==