Goldfire's Lair is the twentieth and final level of Planet Strike. It does not contain a security cube. The player must defeat the Crawler Beast, which drops a keycard. The keycard can then be used to unlock the door to the room in which Dr. Goldfire is waiting. Defeating Goldfire is the final goal. The Goldfire boss does not count towards the enemy destroyed percentage, so it is possible for the player to clear the level and gain a 100% area rating (and also a 100% mission rating) before opening the door that leads to the final showdown.