Collect the five hidden blocks throughout the city to unlock Super Wrestler. The five blocks can be found at the following locations.

On Apollo Island
The block can be found behind the garages along the runway.

On Auburn Bay Bridge
The block can be found on the support beams of the bridge.

Bluebell National Park
You first need to beam up to the top of the dam. Then, chop through the boarded door, and climb the ladder to find the block.

Lego City Airport
The block can be found underneath the freeway near the airport.

Pagoda
Search the walkways along the ocean to find the final block.