I heard zombie growls from underground while gathering Kelp and I got tired of hearing them. Turns out the sea floor wasn't flat. See the torches middle bottom? The sea bed sinks away between the coral and it goes deep! So I went poking for the zombie cave and I found why it was so noisy! Click Here: Close enough to spawn zombies while I was on the surface.
Didn't get a chance to post updates. Made a kill chamber from the spawners. Now have a source of XP to replace burning kelp + fishing. With the habitat prepped my friends were ready to move in. I still to finish the window views. Work on the dome continued today. This is a big project but will look really nice with some interior structures. And I came across this sad fellow while gathering sand for the dome.