Total number of studs needed: 180,000
If you have 100%'d the game before completing this level then just turn on all your stud multipliers, and within the first few seconds of the level you'll reach True Avenger. If you don't have the multipliers then break anything and everything to maximize your stud earnings. The achievement will not pop though until you have completed the level and you going the post-level screens.
Happy stud hunting