Time Gate Piece
Time Gate Pieces can be found rarely when killing Bosses. Once you find a Time Gate Piece, there is a cooldown timer of about 5 days before another one can drop.

Time Gate 6 Pieces
Time Gates UI Button
Once you've collected at least 6 Pieces, you can spend them to open the Time Gates manually, as long as they aren't due to open naturally within the next 72 hours.

Time Gate Piece Card

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