What is Reddit's opinion of ファルキューレの紋章[美少女育成萌えゲーム！]?

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Reverse image search gave this result: Emblem of Falkyrie
Here's also some old article about it and a wiki page listing several cards, including the one from your screenshot.
EDIT: of course there is some chance the game above is a totally different one from the one in your screenshot and they simply reused art through different games. It's not an uncommon practice, especially for mobile games.