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Construction wise this seems impossible as all spike are contained in the blocs. Is it possible that it's related to #1644?
Well, this issue is that a player's bounding box could end up touching both the blocs bounding box and the spike bounding box, causing the issue we see now.
It looks to me like the player is actually extending extra pixels into the blocks when jumping (due to the additional speed), this also seems to happen more consistently at lower frame rates.
We could either shrink the bounding boxes of the roof spikes or hope it's fixed by #1891