Before I let anyone touch any portal, I inspected every portal one by one. If I don't want to mess up the dungeon run and end up being lost for a long time, I needed to check the characteristic of the portals. Soon, I found one portal with a small glow of red in its blue color. It was slight color and it's not really obvious to see but if you try to look at it for a while, you will eventually notice it. That's what the portal we needed to use as that indicates the portal is connected to the final boss and it is the right portal to use if you want to meet him. Of course, that is the first portal and not just a single portal that will immediately send us straight to the final boss.
Since this dungeon always changes every time you enter it, you needed to always check out the signs it gives to fully clear it and master pathfinding the whole place.
"Everyone, I found it, follow me!"