You could use the PPD heraclese. Its the same model, just different color scheme.
Might I suggest the Vanguard Shield/Sword giant robots?
Yeah but it's only available as a boss rank 
. I needed something of Elite Boss or Arch-Villain rank.
- Im Not Talking Fast, You're Just Listening Slow.
- To Each His Own
The only true Giant Robot we currently have available is unfortunately not attackable. But it is giant. All hail the Mega Mech!
Eva Destruction AR/Fire/Munitions Blaster
Darkfire Avenger DM/SD/Body Scrapper
Arc ID#161629 Freaks, Geeks, and Men in Black
Arc ID#431270 Until the End of the World
Vanguard HVAS units are elite bosses - and while not 'giant', they're pretty hefty. 
"If I had Force powers, vacuum or not my cape/clothes/hair would always be blowing in the Dramatic Wind." - Tenzhi
Characters
Perhaps you could make a custom Bots/Whatever MM and say in the story somewhere that this "Doomsday Robot" seperates into pieces when attacking to more efficiently kill/destroy/maim.
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[ QUOTE ]
The only true Giant Robot we currently have available is unfortunately not attackable. But it is giant. All hail the Mega Mech!
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OT: I thoroughly enjoyed that arc. 
The customs looked great.
Okay, I was looking for a giant robot enemy to place in my arc. To my delight, I found the Longbow Catatrophic elite robot, great! I include the robot in my mission, go to test it, and to my displeasurement, every enemy in my arc is now lv54!!
I didn't mind the Longbow robot to be lv54 - in fact, i kind've wanted that, but everything else? C'mon! Needless to say, I threw it out of my mission. The only other giant robot i could find was the Vanguard's HVAS one, but it doesn't really have the "Giant" feel to it ya'kno?
I initially had the Kronos Titan in mind when designed the mission's story but it isn't avaliable. I also attempted to make a really tall/heavy custom robot, but it didn't feel right neither. I just want a Doomsday Weapon in my mish but we have no giant robots that wont completely screw the rest of my mobs up.
My question is, is there a way to make the Longbow Catastraphic not mess up my mission's mobs? Or, is there another giant robot i can get that im not aware of. If i could get the Kronos Titan than that'd be GREAT!! Overall, I just want a giant robot, is that too much to ask?
- Im Not Talking Fast, You're Just Listening Slow.
- To Each His Own