Went back to the final boss with updated stamps and wiped the floor with him. Game done!

Headed into the fourth area and it was something of a difficulty spike... except for the boss. Ran through the fifth area too and the first phase of the final boss was easy but the second phase wore me down. Decided to get the rest of the beats and improve my patches and go back to take the Baron on.

Got this a while back and made a little headway into it but then dropped it for other games. Now I'm back and ploughing through the game - have already beaten the third boss.