Speed King, an arcade puzzle game with battle arena elements set in a fantasy world, challenges a player to help a king retake 100 castles captured by his enemies. The king's world is designed with plastic bricks and blocks. The king is represented by a white head block and a crown.
At each high-walled castle, the player must direct the king from a bridge into a grass-covered courtyard filled with wooden crates. To retake the castle, the player must help the king rapidly destroy all the crates.
The game makes this task extremely difficult in a wide variety of ways. The king can only dash in a straight line in any direction, which means that the player must plan ahead to make certain they choose directions that lead to every crate. They must also deal with deadly weapons and enemies, including a motion-detecting spiked ball that rolls around the yard, sections of spikes along the gray walls, and shooting missiles and laser cannons.
If the player wins, the doors to the inner part of the castle open and gold bars pour out into the courtyard. The game also captures the moment with a snapshot.