The star is the wild symbol, it can land on reels two, three and four and it will substitute for all of the other symbols, except for the scatter symbol, to help and form winning combinations.
The scatter symbol is a horseshoe and it is key to one of the bonus features.
Each horseshoe symbol that lands on the reels has a cash amount associated with it and when you land six or more horseshoe scatter symbols anywhere on the reels, you will win five free spins together with the sum of the horseshoe prizes. This sum becomes the repeating win during the free spins. Each star symbol that lands during the free spins will award you the sum as well as one more free spin.
Lucky U offers a top payout of 500x for landing five of the purple brooch symbols along a payline. The bull can payout up to 200x, and the lion and the mask up to 100x. All of the lower value symbols can also payout up to 100x.