Magnus Lind's initial dabble in level design was with Quake II. Even though he never released any maps for the game, it was the game that spurred his interest for level design in general. When Half-Life was released, Magnus thought that the Worldcraft level editor was great and thus he started playing around with it.
The first map that Magnus Lind released to the public was a map for Team Fortress Classic (another Half-Life mod) called SpyHard. Even though the map was poorly received by the community, it attracted the attention of Jess Cliffe. Cliffe sent an e-mail to Lind asking him to design a map for Counter-Strike for its upcoming first beta release. Magnus initially declined, but quickly changed his mind. Thus, he designed Mansion, which was officially released as part of beta 1.0.
List of maps