The wild symbol is a large red crystal with a ‘W’ engraved in it. It can substitute for all the other symbols to help and form wins.
Upgradium doesn’t have any scatter symbols.
If you land the orange crystal on a ‘Hot Spot’ (marked by a purple background) it triggers the Crystallisation Respin. All the symbols on the reels will be upgraded to the next highest paying symbol on every respin. Furthermore, reels two, three and four become ‘Hot Spots’ during the respins and landing the orange crystal again will retrigger the feature.
Whenever the wild symbol helps to form a win it will also upgrade the winning combination to the next best paying crystal.
Upgradium offers a top payout of 1,000x for landing five wild symbols along a payline. The orange crystal can payout up to 500x, the large yellow crystal can payout up to 400x and the smaller yellow and green crystal can payout up to 300x.