Story Related, can't be missed.
This is obtained after turning in the final story mission. The story consists of:
Professor Nakayama, I Presume?
A-Hunting We Will Go
The Fall of Nakayama
On Normal the final boss should give you no trouble at all:
Jackenstein was actually the highest level creature in my playthrough but still no trouble if you are following the guide and level 50 or above playing on Playthrough 1. Just shoot the metal parts on his back and then defend yourself from Hyperion Loaders for a minute or two, rinse and repeat then shoot him in the chest after both metal protrusions are off his back. Having a character that can distract him would prove helpful as well, whether that is a friend or use Maya (utilize "Thoughtlock"), Axton, Zer0 or Gaige. If following the guide though it is completely not necessary in my opinion.
Note: There are some known glitches related to this trophy please see here: Borderlands 2: Glitches and Fixes