Fighting Yuki Oh Masuda
This fight is in the middle of the game and it tests whether you have been paying attention to Hunt setups. I ran into it around level 79 and my team was underleveled because I had been focusing on social links instead of grinding Palace content. That was a mistake. The battle doesn't care how cool your fusion is. The first phase has her using normal attacks and calculating your patterns. She builds a gauge each time she predicts a move correctly. When that gauge fills, she gets Mind's Eye, which doubles her accuracy and makes her evade a lot of what you throw at her. You need to stop that from happening by applying Hunt before she gets comfortable. Physical skills cause Hunt on hit, so that is your primary tool from the start. Jack Frost, Norn, and Izanagi are fine choices. Use them every turn until Hunt is active.
Persona 5 Royal Okumura Boss Guide
The second phase is where people get confused. She changes appearance, starts nulling all elements, and her calculation behavior becomes more aggressive. The Hunt condition still applies, but she can now drain the Hunt gauge much faster than in phase one. I kept trying to use elemental skills after she nulls them and wasted three turns while her gauge filled. That was on me. Stick to physical or almighty damage after the transformation. Ganesha and Ananta work well because their skills are physical and they hit for solid damage. Don't bother with anything that says fire, ice, bolt, wind, or nuclear. She ignores it. Here is the part most walkthroughs skip. You cannot win this fight purely by surviving until her Hunt gauge runs out. The damage numbers will not be high enough and the fight drags until you run out of MP or healing items. I spent about twenty minutes in phase two before I realized I was barely denting her health. The actual solution is applying Hunt quickly, then stacking physical strikes with no wasted turns. When Hunt is active, her guard breaks on the first physical hit, which stuns her for the rest of that turn. You get free action after that. Use it to apply more Hunt or go all-in with damage skills. If you are playing on hard difficulty, this fight scales her stats more aggressively and her Mind's Eye uptime increases. I found that equipping skills like Brave Blade or Savage Blade on your main attacker made a noticeable difference because they hit multiple times. More hits means more Hunt applications and more chances to break guard. A single big hit is less reliable here.
There is also a minor quirk with her Annul skill. She sometimes uses it right before you would have exploited a weakness, completely wasting a turn of elemental damage. This happens more in phase two than phase one. I stopped using elemental skills entirely after phase one and just committed to physicals. It removed that variable and made the fight much more consistent. You save mental energy when you do not have to react to Annul anymore. Level wise, I would recommend being at least level 80 before attempting this. Below that, you are going to struggle with damage output unless your party is built very specifically for it. There is no real workaround for low levels other than grinding. The game does not give you much mercy here. The boss arena has no useful enemy drops from normal attacks, so do not waste turns attacking once Hunt is established and she is stunned. Use that time to replenish HP or MP, or to set up buffs.buffs like Tarukaja and Rakukaja carry over into phase two, so applying them early is worth it. I usually spend the first two turns building Hunt and the third turn applying buffs if Hunt is already active and she is staggered.
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One more thing about preparation. Stock up on Mediyas and Salvation Tickets before this fight. I walked in with only three mediyas and burned through all of them. You will need more. Bring at least six mediyas, four salvation tickets, and a few power sources or energys if your party runs heavy on SP. If you are having trouble with the Hunt setup, try using skills that hit twice or more. Skills like Brutal Impact or Diarama do not cause Hunt because they are healing. Make sure you are actually using offensive physical skills. This sounds obvious but I watched a video where the player was spamming Diarahan for two minutes wondering why the Hunt gauge never filled. That is basically how you handle Okumura. Apply Hunt early, switch to physical and almighty damage after phase two, manage your supplies, and do not let her get comfortable with Mind's Eye. The fight is straightforward once you accept that elemental strategies stop working halfway through.