Beating the Strawberry Boss gives you a Portal Key. I think it's just a dummy item. To get to the area it unlocks, from the area in Bell where you first see all the awesome blue jello on the ground, go one screen south. There is a green bush stuck in the middle of some purple (and one pink) trees. Slash it, and hop on into the stairs/cave.
When you're in the cave, go north, North again, and go down the stairs. Yes, you do need the hookshot for this. (Oddly, the ice wand doesn't work here. Not sure if bug or not.) Either way, whenever you get the hookshot item, go down the stairs. Then go one screen north, and bomb the wall above the chest.
You'll be well on your way from there, as it's a straight path to the Bell Portal. It's an interesting place, but not much you can do there yet. It's not complete, in other words.
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To get the Hookshot, you'll definitely want to be going through Sandsheer mountains, way up to the north of Tuton Valley. When you get to the dungeon, on the third floor, there will be an extremely inconspicuous block you'll have to push in the northern-central area of the dungeon to open a door. The room with that push-block is under the "F" in the minimap, second row from the top, with two white staircases in it and a dividor of alternatively colored blocks leading off to the right.
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There's absolutely nothing in Fractal Forest. Just a change of scenery, really. Nothing at all is complete, and there is no content except what's on the overworld. It's just really interesting to look at.
Meridian Cave - one creature tells me "hit wall by the bubbly tubes in other room directly to west (of where Wishful Stripe is) " I've talked to some creatures in there who want to eat my head, but not Wishful Stripe himself.....any helpful hint to get to this area alluded to?, do you get the flippers here or some other needed item?? a hookshot would be handy as well...
I don't actually think there is a place on any particular wall where you can strike with the boomerang. But there are places you can get to with the Hookshot (described above) and with the Ice Wand, which I do also believe you can get. That's a really useful thing, the ice wand. Oh god so much, yes, especially in Meridian Cave, where there's almost more water than land. Makes getting around a TON easier.
The Wishful Stripe is found in the southern-central area of the cave. It just needs some floor-buttons pressed to get to. There IS, however, a wall that you can literally walk through. If you label the map with standard 0->7, 0v7 coordinates, it's on room 6,4 - That's the middle vertical map row, second from the right. You walk through the middle of the right side of the room's wall, just below the water. That will definitely help y'all out. I think you've been there though. The stripe that tells you about the bubble tubes apparently has a piece of coral directly to his left. Push that up. It'll lower the orange blocks, enabling you to proceed. I just found that out.

But that is only temporary. In the very same room, when you come in from the left, keep attacking the upper wall with any weapon. I used the Boomerang. With that, you're set!
Helpful tip: Hit F3 to pause the game, and hold F4 to advance the game frame by frame. It gives you much-needed time to think and react. Not easy to attack out of, though.