- Do I have to attach all of the Energy cards that I find using Cryogonal's "Element Chain" attack?
- No. Since you are not revealing the cards to your opponent, you can choose not to attach any Energy cards if you don't want to and put them back into your deck.
Source:
Evolving Skies FAQ; TPCi Rules Team (2021-08-26)
Relevant cards
Note: All applicable cards may not be listed below.SWSH7_43