Fast and cheapest way to get Sid?

Arena shipments. I've had my fair share of data packs and don't think I've ever gotten Sid shards. Focus on arena, you can get 10 a day with average and reasonable attention given to the game. Refill a few battle attempts, get into the #201-500 pocket, and after the first day of 5, you'll be pulling 10/day easy and not losing hair over placement. #2cents