It's a good idea to go for a Tempest Trial 40% unit... But, long term, the Performing Banner is probably going to be the best investment. Powercreep is eventually going to leave Sigurd and friends behind, but the dancers will retain their usefulness.
You should try to summon for Sigurd and Deidre, or for Inigo and P! Azura. All 4 are really good Units.
Although Ayra is one of the best Units in the game, I wouldn suggest summoning for her, because you might end up with 4 Eldigans, before you get 1 Ayra
Go with dancers. They will be always useful and they are limited. My recommendation is at least get Azura or Inigo because we dont have non seasonal green dancers.
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