The Invincatron is the secondary antagonist of the 2005 animated film Tom and Jerry: Blast Off to Mars. It is a parody of giant monsters and alien invaders this colossal robot was activated by Martians after Tom and Jerry both got exposed as Earthlings, which led them to believe Earth was trying to invade Mars.
Thus the Invincatron headed off to Earth and once arriving began its task of literally "cleaning up" the planet, sucking up any humans it came across via a large vacuum and storing them in a giant sack.
Presumably to be sent back to Mars or simply kept indefinitely as prisoners (due to the cartoon nature of Tom and Jerry it was unlikely it had fatal plans for its captives, despite this it was still by far the greatest threat in the entire movie). Ultimately the Invincatron was defeated by Tom, Jerry and Peep using a bone to get Spike into his brain and make it malfunction, destroying it as a result.
Its captives set free and the misunderstanding between Earth and Mars presumably resolved off-screen, by the end of the movie the Invincatron ceased to be a threat to mankind but its hollow shell was used by Spike to exact revenge on Tom feeling horrified and pursued.
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