Intermission (3-4)

Time to do some fund-raising. Go to D-5 and burn down this bush. Inside is a Moblin who will cough up 100 Rupees. Incidentally, you can boomerang the bush on the island as often as you like. Each time you hit it, a Fairy will be revealed.
Now go to E-6. Burn down this bush, and you'll find 100 more Rupees. You should really be rolling in the dough now. Hopefully, you have 330 Rupees now, or at least 250.
Now go to the shop on screen B-5.
Buy yourself the Blue Ring. It's pricey, but it doubles your defense, which is very, very nice.
Hopefully you still have enough Rupees left over to buy the Arrows. If not, you can always come back later, but it's nice to get them sooner rather than later. You'll need to buy the Meat eventually too, but you don't need to now, but feel free to if you still have some money after getting the Blue Ring and Arrows.
One screen to the right of the shop is a dock. What better time to try out your new Raft than now?
How fortunate, it took us right to the location of Dungeon 4...