Doom (1993 video game)
Because id planned to self-publish the game, as the game neared completion they had to set up the systems to sell the game. Jay Wilbur, who had been brought on as CEO and sole member of the business team, planned the marketing and distribution of "Doom". He felt that the mainstream press was uninterested in the game, and as id would make the most money off of copies they sold directly to customers—up to 85 percent of the planned US$40 price—he decided to leverage the shareware market as much as possible, buying only a single ad in any gaming magazine. Instead, he reached out directly to software retailers, offering them copies of the first "Doom" episode for free, allowing them to charge any price for it, in order to spur customer interest in buying the full game directly from id.
Doom (2016 video game)
In all of its platforms except the Nintendo Switch, "Doom" includes a built-in level creation tool called "SnapMap" which allows players to create and edit maps with their own structure and game logic. With SnapMap, players can create maps for different modes, ranging from single-player levels to co-operative or competitive multiplayer maps. When players are building a level, the game will shift to a top-down view. Players can place rooms and hallways to form a level and connect them together. If they are not connected together, the color of the construction pieces changes to notify the player. Players can also use the X-ray camera which temporarily removes all the walls to allow players to view the objects inside. Players can also place enemies into their maps, with the exception of the campaign's bosses. Their artificial intelligence and stats, and the player's own movement speed can also be modified. Players can also add additional particle effects, lighting effects, and other gameplay items, such as health packs and ammo pick-ups. Only in-game assets can be used, and players cannot create or import their own models into the game. Levels can be tested before they are published online.