
What is funny, the creator has sent a demo version to Broderbund and the company rejected his offer of cooperation. Smith got the loan and reworked the game, and only after a second try he got the approval for the release of an improved program under the new name of Lode Runner.
Clones were many, for example: I started to play "Tarzan", but only in 1994 (!) Sierra has released a sequel, which was different from the usual game play, because there was possibility to play with another player and had a large number of traps.