There are three kinds of Shards you can collect: wild, random, and regular.
You can exchange 100 Shards for a legendary card, according to the kind of Shards:

  1. Wild shards: You can exchange 100 wild shards for one legendary card of your choice.
  2. Random shards: You can exchange 100 wild shards for one random legendary card.  
  3. Regular shards: There are 10 types of regular shards, each corresponding to one of the 10 legendary Club cards. By exchanging 100 regular shards, you can obtain the corresponding legendary card.

You can win Shards by: 

  • Playing matches in Stage or Tournament game modes
  • As Rewards for completing Quests in the Challenge Pass
  • Different Game Events