There are numerous slot machines where the authors placed their bets on visuals or higher winnings in the base game. But if the game has sloppy bonuses, it’s unlikely to become a hit. To exemplify this, try to recall your favorite games and then decide for yourselves what was your favorite part in them. Bonuses will surely be located near the top of your ranking.
Today there are thousands of online slot machines, but there are significantly fewer types of bonuses. And so we as well as players can appreciate the originality and creativity of those authors who can create something new even in this particular area.
However, as long as we stick to the classics, the most frequent types of bonuses are the following:
Wild symbol
The most classical (and a highly popular) bonus - one that occurs in virtually all online slot machines. Its elementary part is a special symbol which works as a joker in the base game. This means that if one symbol is missing in your winning line and its position is taken by the Wild symbol, the slot machine will evaluate the line as complete and pay out your winnings, often even with some small bonus for using the Wild symbol.
Expanding wild symbol
A special type of Wild symbol which works in a same way as a classical wild symbol. However, its specialty is that once it appears on any field, it expands. This means that it also appears in its surrounding fields, leading to the possibility of creating additional winning lines.
Scatter symbol
A second well-established classic and faithful companion of the wild symbol. This is another special symbol that can be found in virtually every game. It is often used to start a bonus game that is linked specifically to this symbol. To do so, you need to get the scatter symbol at least three times, anywhere in the playing field - this usually suffices to start a bonus game. Of course, in some cases it can also operate on its own, whereas it rewards players with a nice bonus as soon as it appears.
Free Spins
Does there exist a more popular bonus than free spins? Well, honestly, that’s a tough question. Free spins are quick, simple, and generous - and they don't cost anything. What else could a player want? Nothing, really. If you manage to get some, make use of them. And if the game authors were generous and allowed you to also accumulate other bonuses during your free spins, then the result is truly spectacular. The only disadvantage is that there’s usually a very small number of such free spins.
Multiplier
There are many ways a multiplier can operate. However, they usually multiply your final winning by a certain value (x3, x5, x9 or x15). More often than not, this bonus depends on how well you succeed in chaining winnings. It is very frequent in slot machines where spinning reels are replaced by, e.g., falling rocks which explode after obtaining a winning combination. In this case, each explosion is followed by an increase of the multiplier. Multipliers can however also be linked to other things, such as bonuses, free spins etc. Creative designers know how to use this bonus well in order to create truly interesting possibilities of achieving high prizes.
Click and Pick
This bonus is often linked to other bonuses (probably most frequently to the scatter symbol), or comes with its own special symbol. It basically consists of a separate bonus game where your task is to choose one or several items, each of which represent certain hidden bonuses. This is a highly popular type of bonus, since it’s virtually impossible to lose in it. You can only gain. It is sometimes also connected with an additional level. In that case, one of the items represents an entrance to another minigame. This used to be one of the most frequent bonuses, but is a bit less frequent in newer games.