Robot Alchemic Drive for the PS2.
The plot was horrible, it revolved around you being the heir of this odd foundation that made three giant warmachines, and space being full of radiation that killed everything no matter how you tried to shield it, and aliens invading earth.
Voice acting was beyond bad, seriously, I'm sure there are youtube clips, they are bad.
Controls were weird.
But despite it all, it was a freakin' blast to drive a giant robot around a city and engage in huge knockdown dragout frights with giant space monsters. Game got way too much flak from people for it to be that fun.