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, and so on) in mana costs of permanents you control don’t count toward your devotion to any color.Thassa, Deep-Dwelling turns the end of your turn into another use of a creature's entry ability. She exiles up to one other creature you control, then returns it under your control. Spellseeker can find another cheap spell, Solemn Simulacrum can search for another basic land, and Skyclave Apparition can exchange another opposing permanent for its eventual Illusion compensation.
The blink can also reset counters or remove attachments, which is useful or costly depending on the target. A creature you temporarily stole returns under your control through Thassa's instruction, potentially letting you keep it beyond the original control effect's duration. Tokens do not return after leaving, so blinking a valuable token is usually a loss rather than a way to preserve it.
Indestructible helps the enchantment survive destruction, and she becomes a creature only while your devotion to blue is at least five. Her four-mana tap ability can clear a blocker or delay an attacker, giving spare mana another use when you do not need a new spell. The engine does not produce creatures by itself, so a deck needs worthwhile blink targets rather than expecting Thassa alone to refill its hand. Deploy her before your end step when a useful target is already present, and select that target based on the next turn's needs rather than automatically repeating the largest entry effect available.
