So in Champions Online there was a travel power called Tunnelling. It basically worked like Super Speed (but slower) does now but the character travelled underground (basically stealthed) and there was a trail of cracked, raised dirt (similar to the Seismic aura) to show their progression. I have seen others suggest this as a reskinned teleport but that does not really feel right. I am uncertain as to what other power might go with it in the pool. Maybe a single target, melee, immobilize. Maybe a single target Slow like Quicksand. You could do a group tunnel where the rest of the party follows single file behind the power user like they were following inside the tunnel.