There are two transporter parts, so I'm just gonna go ahead and assume that you're stuck on the first one.
To solve the puzzle, just follow these seven easy steps!
1. Pop transporter #1 and wait until it hits the bottom wall.
2. Step into the spring above where transporter #1 was and Pop transporters #2 and #3 while you're airborne. If done correctly, you should land on transporter #1 and it should stop at transporter #2.
3. Pop transporter #2 so that it hits the left wall.
4. Step on transporter #3. When you hit the spring at the right wall, you should bounce back and land on transporter #2, which will take you back to transporter #3.
5. Pop transporter #4 twice so that it rests at the bottom wall.
6. Pop transporter #5 once and ride it to the top wall. Once you hit the spring, Pop transporter #6 so that it heads to the right wall. Also make sure you Pop transporter #2 to get it out of the way. If done correctly, you should land on transporter #4 and get taken back up to transporters #5 and #6.
7. Step onto transporter #6 to use the spring and get launched past the cage. After that, you may claim your key!
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