Every event only has certain bears that you can win. See this page to learn how you can determine which bears are available from a particular event.
If you score in the appropriate tier (Silver Egg or Gold Egg), then the bear you receive is randomly chosen from the bears awarded in that tier. Note that, while it is random, not all bears have an equal chance of being awarded—the more powerful bears generally drop less frequently than the less powerful bears.
Article is closed for comments.