The act of killing the opposing team in a base, often uncapturable, but sometimes also of the capable variety. Often uses the most 'invincible' weapon available, such as a tank or a siege weapon.
National Hero: Agh! We're losing!
Royal Team: BASE RAPE TEH NUBS!
National Team: Noooo!
Person A: Why do they call it "base raping?"
Person B: Because it's like forcing someone to have sex with you. It might feel good for the perpetrator, but the other people of the world think it's wrong.
In the Dynasty Warriors series of video games, going around from base to base and slaughtering people, esp. the four Guard Captains in order to gain control of that base.
It's so easy to win, all I do is go around base raping.
Random guy: "Just because we're a supply base doesn't mean we cant fight!"
Lu Bu: "STFU and die bitches."
*rapes the base*
Lu Bu: "Can anybody provide me with a decent challenge?"