My take on how to easily defeat Corrupt monk and O'rin of water.
My first souls like game and first playthrough, so I'm not sure if there are other efficient ways to defeat them.
Honestly, sekiro is a weird game for me.
One day, you are stuck for hours on a single boss and next day, it's easy to defeat them like taking a walk.
O'rin of water: Need mortal blade.
Walk up and stand in front of her, don't open dialogue and do two slashes of mortal blade.
Now back off, she will come with her strikes. Hold deflect or try to perry them, wait for the sweep attack and do a head jump. Not only does this do posture damage to her, we also get enough time to do two slashes of mortal blade, that's the main attack window.
Just do two slashes and back off, at this point your posture will be high so recover it.
And repeat the steps.
It's simple, took me around 5 minutes and killed her easily on my second attempt.
Although her second phase requires more patience. She will continue to do attacks and sweeps are less this time, understand her pattern where she waited a second or two between strike rhythm and attack with mortal blade
Corrupt Monk: 3 snap seeds, mortal blade, 10 ashes, ako or ungo sugar(not mandatory), atleast 5 gourds.
I can't believe i wasted 3 divine confetti, 7 snap seeds and remain stuck on her for two days, I'm feeling so stupid.
We don't even need divine confetti, just pop a ungo sugar and run towards her.
Use snap seeds and strike 3-4 times, repeat till snap seeds don't have effect. Which is after 3 snap seeds.
Her health is down by 35% or so, now spam fire crackers which opens window for 2-3 normal slashes.
Use all your firecrackers and repeat this pattern.
Her health should be down by another 20% or so, werl i keep getting attack by her due to my greed of landing attacks so I wasted half of window created by firecrackers getting to stand up after being stuck in sweep attack.
Anyway, after her health is below 50%, she gets aggressive. Pop an ako sugar and switch ot ashs.
Use ash to get hit windows and use two slashes of mortal blade, run backwards to get a breath so you can relax.
Repeat.
Literally, use jumps and hold deflect to survive her continuous spear swings or slashes.
Pop an ungo sugar if she is not dead yet and ako's sugar effect ran out.
Took me a ressuraction and 5 gourds, it's upto your skills on resources required.