You will have to play close attention to the two Don Medusas on the bottom of the room as you attempt to clear this round. Start out by carefully collecting the two Heart Frames above the right Don Medusa, using the boulder for protection.
When the right Don Medusa is headed to the right, push the nearby Emerald Frame up one space, then wait behind the boulder for the Don Medusa to head right again, and push the Emerald Frame all the way to the left. Carefully come back to the right and take the lower path to get beneath the Emerald Frame, now watching out for the left Don Medusa, and push it up next to the Medusa above.
Head over to the bridge, and cross it to the grass above. Be aware of the Rockys' positions as you move through the grass so that that do not force you to walk out into the open where a Don Medusa will see you (the Heart Frame in the upper right corner is the last one to be taken).
Stand against the top wall on the vertical strip of grass so that the Alma rolls over to you and starts moving up and down above the Medusa. When it is on its way down, head to the left (wait for the Don Medusa to head to the right).
Collecting the next two Heart Frames requires good speed and observation. Since the Heart Frames across the water are present, they protect you from the Don Medusa below, but the Alma will come quickly so you cannot wait too long to collect them. It is best to do it in two shots, collecting one, and then running back to the strip of grass. Then run out and grab the other Heart Frame before the Alma returns.
Make sure the Alma is running up and down above the Medusa before you attempt to run back to the right. Then pass by the two Rockys and cross the bridge.
Carefully position yourself between the two boulders below the Medusa, and when the left Don Medusa is heading to right, collect the Heart Frames on the left one at a time (that is, collect the left one, return to safety, then get the right one, and come back).
Collect the last Heart Frame, in the top-right corner. Then pass by the two Rockys, cross the bridge, and immediately run to the left to reach the key before you get burned by the Gol's fireball.
Collect the only two Heart Frames on either side of you. The following solution can be executed on either side of the room, but it's a little easier to try whatever side the Rocky is not on, typically the right side, so this walkthrough will explain the steps on the right. The mirror image will also work.
Push the Emerald Frame above the right where the Heart Frame was to the right until it is above the boulder. Wait for the Don Medusa to reach the lower right corner of the room, and push the frame one more space to the right to trap it in.
Walk up the right wall until you reach the Emerald Frame that is below and to the right of the right Medusa. Watching the movement of the right Don Medusa above you, push that frame one space to the left to block the Medusa's view below, and then quickly step in between the Emerald Frames.
Walk up to the boulder to your left (to the right of the center Medusa) and push the Emerald Frame above you one space up to block the right Medusa's view to the left. As long as you watch out for the Don Medusa on the left wall, you should be able to safely reach the key.
Wait for the center Don Medusa to move a bit to the right, then walk along the bottom wall, push the lowest Emerald Frame to the right, and push the one above it up one space.
Carefully make your way two spaces to the right, where you are protected by a boulder. Collect the single Heart Frame when all of the horizontally moving Don Medusas are moving to the left, and then scurry back to the protection of the boulder.
Choosing your timing carefully, the next step is to approach the two Emerald Frames in the center of the room, push the right frame up one space, and push the left frame over two spaces so that you trap the left Don Medusa near the bottom of the room. Don't hold still because you can still be seen by the upper Don Medusa, so get to the left wall and duck behind the boulders for safety.
Walk up to the Emerald Frams above, push the left one up one space, and push the right frame to the right three spaces, and collect the key when it's safe.
Push the lowest Emerald Frame up one space, but leave the lowest Heart Frame alone for now.
Collect the two other Heart Frames on the left. Then stand below the lower Emerald Frame on the left, and push it up three spaces.
Walk over to the Emerlad Frame on the right, and push it up one space below another frame. Then come back to the frame in the middle and push it up exactly two and a half spaces so that it stops halfway between the boulder and the Medusa above.
Come back to the left side of the Emerald Frame you previously pushed up, and push it left one space. Then push the highest Emerald Frame up exactly two and a half spaces, so that it sits in between both the top Medusa on the right and the treasure chest on the left.
Head down and collect the last Heart Frame. The Gols will wake up, but you should be able to move quickly enough up the screen and between the two Emerald Frames at the top to reach the key before they can hurt you with their fireballs.
Push the Emerald Frame along the bottom wall in two spaces and collect the Heart Frame near the lower right corner.
Of the trio of Emerald Frames near the Medusas, push the lowest one left two spaces and up one to block the lowest Medusa's view to the right.
Push the right Emerlad Frame up two spaces to block the middle Medusa's view to the right.
Push the remaining Emerald Frame right two spaces, up three spaces, and left exactly one and a half spaces (if you try to push it two spaces, the top Medusa will kill you.)
Now you can walk around the right side of the room to the top portion. Stand to the right of the Emerald Frame below the chest, and push it left one space. Then stand above it and push it down one space.
Now you can safely collect the last two Heart Frames and the key.