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I have been trying to download the latest version of Calamity but it just gets stuck at a full progress bar.
tModLoader version: v0.11.5
Terraria version: 126.96.36.199
OS: Windows 10
Edit: I somehow managed to download it again.
I encountered, when looking through my chests in my single player world, a purple rarity Celebration. But it was like no other purple rarity Celebration. It had no modifiers. When I looked at it the next morning, it returned to red again. Here's the proof: