i don't think sending a box to the past but the box doesn't ever get retrieved from the past shouldn't be a paradox, i think it should be, if possible can you make it so doing that causes a paradox?
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I could, and it started that way, but the only way to really make this work would be to prevent boxes font being sent if they weren't retrieved in the first place. And technically, sending something doesn't mean it has to be received, though the opposite isn't true, so yeah I went with the simpler version.