Some sort of demonic snake-beast

You stumble headlong into the science lab, trying desperately not to fall, land on your face or rip your bio-suit. It's nearly hopeless, you crash into a science desk, sending test tubes and stacks of paper crashing to the ground but use the edge to steady yourself.

The whistle sounds again, from behind you, loud enough to make your ears ring and leave you feeling dizzy.

Clumsily, you turn around, putting you back to the desk as you try to get a look at what hit you. Something huge slithers into the room and through the door way as you watch. It is at least three or four times your size.

The snake-like monster has rows of arms, three on each side, six in total near the top of its body. Purple and green scales covers the length of its body. The details of its tail are hidden in the thick red fog that billows into the school's science rooms.

The head of the monster is a scene from a nightmare. Curling horns curl backwards over a huge head. Strangely human looking eyes. A jaw that looks like it might have come from a lion or other large cat, with giant fangs and a lolling tongue.

Despite it's size and length it quickly pours into the room. It doesn't head straight for you, thank goodness, it seems to crawl to the left but as the red fog thickens and rises it becomes hard to see.

You've a choice. You could dash forwards, bravely towards the door you've just been pushed through and try to flee. If you don't want to risk that then perhaps hiding somewhere in the lab, as the fog pumps in, might be a better idea.