Grand Battle (S?) (Round 1: SUDDEN DEATH)

Tom loomed over the edge of the spiral staircase, looking downward. It was dark all the way down.

His head hurt for a moment, and his vision shifted. He was suddenly staring far down into the darkness, except it was not dark. It was water. A deep, deep body of water.

"...Another strange modification, Sir?" Tom murmured. "I certainly don't mind, but I would have appreciated if you asked...

He saw blurs of motion below. It darted under part of the spiral staircase, which tapered further into the water.

"Hello?" he called out to the abyss.

There was no movement below, but he heard muffled chatter from the room across from him.

Tom pretended not to notice the chatter as his eyesight went back to normal. Maybe his company had not meant him to hear. His hearing had become rather strong one day- probably another one of his master's strange whims- and it wasn't courteous to be aware of private conversation.

Moments later, four blue figures came through the door. They seemed to be mermaids, but with seamless blue flesh, elongated skulls, and several protruding fins. Coral breathing masks covered their mouths, and were connected to packs resting on their backs. Their fish like lower halves rested on large coral spider figures. All four of them seemed to be wearing some form of smock.

Tom connected some dots.
The tower belonged to these people.
They used coral spiders to walk in areas that were not water.
The massive scale of this building, and the fact that he saw movement below, meant that there was probably an entire people like these four.
Their lack of weapons indicated that they were builders, and probably were not here to fight.

The last point really was the most important.

Slowly, Tom raised his arms non-threateningly above his head. He spoke slowly and deliberately "I'm here in peace." He did not think that they would understand him, but he hoped his tone would convey his meaning.

The smallest of them began to gibber excitedly. The second largest and and most slender of them voiced something sharp, but the smallest already began approaching Tom gleefully. Tom gave a small smile. Thank goodness.

An earthshattering CRUNG broke the mood, and the left wall. Tons of water destroyed the room's structural integrity and swept into the room.
The four surprisingly stood their ground easily- it seemed their spider legs had anchored them to the ground.

Tom however was washed away. Instinct screamed at him. He began screaming. The nodes at his shoulders unhinged, and the sides of his mouth slit open, opening his jaws wider and wider. The slits expanded down his throat, reaching the nodes, opening his giant chest mouth- one of his master's latest horrifying additions. Water slammed into him, flooding the room, filling his mouth, threatening to drown him. However, the water entering his mouth seemed to drain down infinitely, and the rest of the water flowed down the staircase, filling it.

The room was breathable again. Tom rehinged and closed his chest mouth, and then carefully traced the slits of his mouth up his collar, up his neck, across his cheeks to his real mouth.

He glanced at the four mermaid beings. They were no longer ready to approach him. He sighed. His master's strange modifications had not done any good to his approachability. Tom raised his hands again, but the four simply reacted in apprehension. Then, one of them glanced at the broken wall.
Tom followed its gaze. A giant white round ball seemed to have jammed itself into the wall, sealing it. Tom was thankful for that much at least. He was pretty sure his chest mouth wasn't bottomless, regardless of how much it seemed to hold.
This orb was cracked as well. Was that what had caused the damage in the first place?

The four beings began a garbled screaming and dived off of their spiders into the water. Tom watched them go, confused. What was the problem?

The orb cracked further. The entire front piece fell off, revealing a bright orange rough surface. What was it, Tom wondered. The only thing worth noting was the slit running across it.

Then the slit opened.

Oh, Tom thought, looking at the insides of the thing. It was a giant orange clam.

Then it screamed. Tom heard only the beginning before his ears burst.

And, for the third time in recent memory, things went dark.