The sun is the wild symbol, it can substitute for all the other symbols, except the scatter, to help and form winning combinations
The scatter symbol features a red spaceship and it is key to the free spins.
Every time that the spaceship scatter symbol lands on the reels you are awarded three Supernova Spins. During these spins more spaceships can land and this will award you a further free spins. During the spins the spaceships act as wild symbols that are two positions high. They will remain on the reels during the Supernova Spins but they can shift position on the reels to help you form more wins.
Solar Se7en offers a top payout of 800x available for landing five sevens or five wilds across a payline. The spacewoman can payout up to 200x, the purple alien can payout up to 150x, the scary alien can payout up to 100x, the triangle can payout up to 50x and all the fruit can payout up to 40x.