There are a few different ways to obtain the Demacian Silverwings. The first is probably the easiest and most convenient, but also the most expensive. You can buy series one eggs until you get a Demacian Silverwing, or until you get the specific Demacian Silverwing of your choice. Each egg costs 490 RP, which is under 5 dollars worth. However, League requires that you purchase at least 650 RP (5 dollars) at a time, so even if you get a Silverwing on your first try, it will be 5 dollars. Of course, you aren't guaranteed to get a Silverwing out of your first egg, or even your first few. If you are looking for a specific Demacian Silverwing, expect to pay anywhere from ten to twenty dollars for it. The other way you can get a Silverwing is to purchase a battle pass (or play a lot of games) when League has a promotional event going on. League of Legends typically has mission-based events where players can earn tokens every few months. Riot has been giving players the option to spend their tokens on TFT little legends. For a random little legend, it will cost 300 tokens, which is probably about 5 hours of gameplay. For a more specific egg, such as a series one egg, it will cost 600 tokens.