Colosseum - "Kong's Fate" Achievement/Trophy

"Kong's Fate" requires you to "make the gorilla from the arena die at the highest point possible." This isn't the highest point in the arena, just the highest point that a gorilla will climb. Specifically, the third highest block in the dark area to the right of the EMPEROR'S BOX (i.e., the tier above the one with the slope). Luring a gorilla to this point isn't especially difficult, but it's easier if there's only one gorilla chasing you. It also doesn't matter which gorilla you use.

If you're also attempting the "Ave, Lara!" achievement/trophy, there will be 7 arena animals (6 lions and a gorilla) alive after you complete the ROOM WITH TIMED GATES AND PRESSURE PADS and climb up inside the ROCK PILE (here in the main walkthrough). SAVE THE GAME HERE. (THIS IS VERY IMPORTANT, SINCE YOU'LL KILL ONE OF THE GORILLAS YOU NEED FOR THE OTHER ACHIEVEMENT/TROPHY.) Then take a running jump from the first rock pile onto the next pile, but don't head for the EMPEROR'S BOX yet. Instead run straight up the rocks and start climbing the tiered blocks. The gorilla should pursue Lara. (Skip the next two screenshots and pick up the guide below.)

If you're killing the arena animals as you go, "Kong's Fate" is probably easiest with the gorilla that appears after you take the RUSTY KEY (here in the main walkthrough). This gorilla is on its own, and you need to climb up to the EMPEROR'S BOX at this point anyway. So make your way there, using the curved jump from the seating area (detailed here).

Then cross the balcony and take a standing jump down to the rock pile. At this point, the gorilla should have already noticed Lara and started climbing around on the rocks below. If not, just linger on the flat spot at the top of the rock pile and it will soon notice.

Now climb up twice. Lara should be standing on the level above the one with the slope.

The other screenshots were brightened quite a lot in Photoshop. The actual game is much darker. So if you're having trouble, try switching to classic graphics. (F1 on keyboard, Options button on PS4/5, Menu button on Xbox, Plus (+) on Switch).

Stand on the ledge above the one with the slope, ready weapons, and wait for the gorilla to climb up next to Lara. Then blast it. (One shotgun shell at close range will do the trick.)

The achievement/trophy should then unlock.

If you're going for "Ave, Lara!" as well, reload your previous save. Lara will be where you left her, and the gorilla will still be alive.

[Colosseum Footnote]