One of Mass Effect's shocking moments comes when you visit a dead Reaper orbiting the planet Mnemosyne. Cerberus had previously sent a different team here to investgate, but lost contact with them. Shepard and his team are sent to find the missing squad, but discover the derelict Reaper's indoctrination mechanism is still active. It turns into a race against time to destroy the Reaper's core and leave before Shepard and his crew become indoctrinated.
After Shepard blows up the core, the Reaper gets pulled into the planet's atmosphere.
