Since there are 50 paylines on 5 reels and landing symbols on any of the lines, continuous running from the left only requires rewards in the base game, but special bonus symbols can also help.
A green ball has no obvious dragon links, but it doesn't matter, because it's a useful scatter symbol that triggers a free spin bonus game when it stops simultaneously in any 3 or more places. If only 3 appear, the player will see 8 additional games, and 4 scatters will roll out 15 spins. The best option is 5 or more, as this sees the beginning of 20 free games.