After acquiring the Eagle's Talon technique, I dived into an underwater cavern where aggressive piranhas killed me repeatedly. After memorizing their patrol paths to escape, I returned to the Kuwak Yaku forest, intercepted a Trinity patrol, and successfully hoisted a soldier into the trees using my new rope arrow skill.
Before leaving the cavern, I found Eagle's Talon technique, which would help me to use a rope arrow to kill and string up an enemy while on a branch. I had to interact with the ancient stone marker to absorb the survival technique.
Then I went ahead and found the only way out of this cavern, and I had to try a big jump toward a pit below, leaping out blindly into the deep shadow of the underwater.
I started diving ahead, looking for trapped air, and when I found one, I was diving toward it, but suddenly, those hungry piranhas caught me off guard and killed me in an instant.
It was... at the restart, when I found trapped air, so I dived toward that gap first and took some air, pulling myself up into the narrow pocket of trapped oxygen along the ceiling.
Then I was looking for a way out, but it looked like the whole underwater was filled with those hungry piranhas, and I got eaten up once more, as I failed to slip past that area before they turned on me.
I had to be careful next, and as I already noticed some movement paths of the piranhas, I could go a little farther this time, weaving quietly between the thick patches of underwater weeds to break their line of sight.
But when I thought I was going to escape the place this time, I was taken down by those piranhas once again, and again, and again, getting trapped in the tight corners of the flooded tunnel right before the exit.
After getting killed by those deadly piranhas for about five or six times, I at last found a way to get fresh air, and now I had to return to Kuwak Yaku.
After getting out of the water, I started moving ahead, and suddenly I noticed there were two Trinity soldiers inside the forest, who was talking through the comms, and letting them know they have been ambushed.
While I stayed quiet on a tree branch, I used Eagle's Talon to fire a rope arrow into an enemy and hoisted him up and killed him, which was the easiest and coolest kill I got in this game till now.