Finally completed the game after 34 hours of playtime.
Defeating Magatsu-Kyuubi in difficulty 10 was a pain. Went in co-op with my bro and finally beat the mission on our 3rd attempt, which took around 25 minutes.
Finally got the Platinum after beating Magatsu-Kyuubi. Currently trying to craft more rank 7 and above weapons and also trying out boost hammer and charge spear before moving on to another game.