There isn’t a huge number of features in Fire Portals but the ones that are there are very good, with persistent wilds that merge and move around the grid with potentially spectacular results. Here is how it works
Tumble Wins
The classic Tumble Wins feature is in full effect here. After any winning spin, winning symbols are removed from the grid in mini explosions. Existing symbols drop down to fill any gaps left behind and new symbols drop down into the grid from above to fill remaining spaces. If more wins are created, then the process repeats. And so on, until no more wins are formed. Then a payout is made for all wins from the initial spin and subsequent tumbles.
Fire Portal Wilds and Multipliers
The Fire Portal Wilds are integral to the game. When a winning cluster is formed, after the symbols in the cluster explode, then ONE position is taken up by a Fire Portal. It is given a multiplier value of 1x and that value will increase by 1x every time the Fire Portal is used in a win.
The Fire Portal moves one place up, down, left or right with each win, always staying within the cluster area of the win it was just a part of, and its multiplier is applied to that win too.
You will also notice that if a cluster already contains a wild, then when the winning symbols are removed, a new Fire Portal is NOT added in that area.
Fire Portal Wilds get more powerful though when two or more appear in a winning cluster. Then, when the winning symbols are removed, the Fire Portals all MERGE and their multipliers combine like this: a 2x and a 5x become a 10x, or a 5x and a 4x become a 20x. And so on.
The Fire Portal Wilds remain on the grid as tumble after tumble plays out, merging, growing their multipliers and moving with each win, until the sequence ends.
Free Spins With Persistent Fire Portals
The Free Spins round is triggered by landing the spell book scatter. When 3, 4, 5, 6 or 7 scatters land then 10, 12, 14, 16 or 18 spins are awarded.
The important part about the free spins round is that any Fire Portal Wilds that were on the grid when the round triggered are carried over AND between spins, Fire Portal Wilds do NOT disappear. So, you can keep adding more and more, and keep increasing their multipliers higher and higher. Powerful stuff!
Better still, this one also comes with re-triggers so you can claim another set of free spins by landing scatters in the same way that you triggered the round in the first place.