Quest for the Nurturing Warmth

North Horon: Start by heading to the screen in North Horon where you first met Din. From there, go down and jump over the gap. You'll land in the water/ice area, so just keep heading down.

Eyeglass Lake: Continue heading right until you reach Eyeglass Lake. Go into the vortex you find there; it'll take you to Subrosia.

Subrosia Village & Lava Lake: Once in Subrosia, make your way roughly south. When you reach the volcano, follow the lava flow all the way to where a Bomb Flower is located. Use your Power Bracelet to uproot it. Now, backtrack to the screen just above the volcano. From there, go left, then left again, and then up. You'll see a stone; pick it up. Use a combination of the Pegasus Seeds and Roc's Feather to jump over the gap. After that, go left and then head up.

The Temple of Seasons: Your next destination is The Temple of Seasons. Head west to get there. Once inside, make your way to the Autumn Tower, located in the North East section. Find the Furnace Chief – he's the one wearing a headband. Talk to him, and he'll use the Flower Bomb you found to open the entrance to the Autumn Tower. Head on up and claim the final Power of the Seasons for your Rod of Seasons! Now, you'll need to backtrack to the vortex you originally came from and jump into it to return to the Overworld.

Eyeglass Lake (Return): Back in the Overworld, head up from where you arrived. When you reach a stump, change the Season to Autumn. To get to the Unicorn's Cave, head up, then right. You'll need to pick up the Mushrooms blocking your path.