The obelisk is reacting to the presence of the artifacts with even more intensity than I expected. Each obelisk on the Island required eight artifacts to generate that sort of response, not three. In other words, I may not need to do any spelunking before summoning whatever terrifying beast this ARK has in store for me.
Ah, the beast. Now that poses entirely different conundrum. Even with my youth and my favorite pipe, I doubt that I could slay a monster such as that dragon Mister Nerva fought. Not alone, anyway. I shall need to find a partner for this venture, but who?