When you arrive in Goron City, you learn that a rift swallowed up the new Chief. You go in to find Tri's friends and repair the rift.

Find Tri's Friends, Part 1

Beware of bombs falling from above. Go southwest to the island with the dark Mini-Moldorm on it. Defeat the Mini-Moldorm and check on the glowing object to rescue one of Tri's friends.

Find Tri's Friends, Part 2

Go northwest and climb up the rock walls, and make your way up the islands. Near the top, you find the monster that spits bombs. Defeat it (you can bind to it to pull it closer to you) and learn the Zirro echo.

Use echoes to reach the top of this area, then check on the glowing object to rescue another of Tri's friends.

Find Tri's Friends, Part 3

Go down below until you can go north to another island, where a glowing object is on top of a circular rock with a target painted on it. Check on the glowing object to rescue another of Tri's friends.

Find Tri's Friends, Part 4

Go east, then south to where there is a Torch Slug. Defeat it, then go southeast to the island where you can reach the top of a stone jar shaped like a Goron. Go down the ladder in the jar. Create a Zirro echo and it will create bombs. The bombs won't hurt you if they are from the echo that you created. You can pick up and throw the bombs that the Zirro creates.

When you break a path through the rocks, check on the glowing object at the bottom to rescue the last of Tri's friends.

There will be a cutscene. Tri's level gauge will increase. You receive 2 Might Crystals. Then you can explore Goron City.