Scorched-earth defense
The scorched-earth defense is a form of risk arbitrage and anti-takeover strategy.
Scorched Earth (video game)
The last version (1.50) was not released until 1995. In 1.5, the registration feature was removed and instead, only a shareware version was released freely while the registered version could only be obtained through a mail order. Purchasing the registered version allowed the player to use the triple-turreted tank as well as removing the shareware reminders. New to this version were lasers and SuperMags as well as a couple of new skies and the introduction of scanned mountain ranges.