If you use cheats in Starcraft 2 to make yourself invincible, you can make very interesting things happen -- "bugs" that the programmers wouldn't have thought of simply because you don't plan for people to cheat

1. "Hey, I'm stuck!  Get me out of here!"  -- Although there are several missions where you can block computer-controlled objects after making yourself invincible, the one I like the most is using Siege Tanks to block the bridges in "The Mobeius Factor."  After you block Kerrigan using tanks in siege mode, the timer doesn't pause -- so when it reaches zero it invalidly assumes that Kerrigan has reached a building that you were supposed to destroy.  (The mission doesn't end, it's just the timer goofed up)  Furthermore, when Kerrigan attacks these tanks, it's like she's lost her temper -- "GET OUT OF MY WAY YOU FOOLS!"

2.  "Oh-oh-oh-oh--I'M FLYIING!" -- In the mission where the protoss mothership is cleansing the colony, if you place a land unit under it's "planet cracker,"  the mothership will leave a great hole on which your land unit will simply "hover."  It won't fall down the hole!  Not that it's supposed to, but it's interesting to see that gravity doesn't exist in that one spot, lol

3. In the mission where you have to fill the zerg tunnels with lava, it's fun to be completely engulfed with lava and yet still be able to move around.  In fact, it's fun to watch the lava rise and slowly get covered with pink fog -- try it!

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