Hey, I just had a thought!
What if that's the Zoanoid mode of Pan? We've seen most of the inhabitants from before (except for the Werewolf) but not him, and he seems pretty much the only other person on the island capable of engaging in a normal conversation apart from the Fairy (Tinkerbell?). Yeah, ok, the mermaids, but they seem kinda dangerous to me.
But the only other time we saw Pan, he seemed contemplative and bored. He might be happy of the company.
I am betting right now that next month, this armored monster turns into the amicable-looking Pan. Why did he spy on them in Zoanoid mode, and did not attempt to contact them? Well, look at it this way: the only other human-looking beings he is likely to have ever seen are Hamilcar Barcas, Imakarum Mirabilis and Archanfel.
But when these two were attacked by the Smilodons, they didn't adopt a fearsome battle mode or simply blast the felines with an energy attack; instead one cowered and the other attempted to fend them off with a pointy stick. They're obviously not a threat. If they're not dangerous, he wants to know more about them.