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Singleplayer Four Portals Concept Chambers

Those are 4 portals in Singleplayer. Those portal colors may be placeholders, but the portal lights would seem odd, but it needs to be a unique linkage color, otherwise, there would be confusion on which portal links to. It's a concept of Co-op portals in Single Player.

The portals aren't perfect, but it's the best I gotten so far. I only wish the visuals of Co-op Portals to be implemented to 2 Portal IDs, but it's always Blue and orange from each linkage.