This is the Hong Kong Whip Scorpion, also known as Vinegaroons.
yes, they are quite large and spooky looking, and yes, they are arachnids, with 8 legs but they only use 6 of them to walk. The first pair are considerably longer and thinner than the rest and used as antennae.
They do look a lot like a scorpion, but they have no venom glands, and instead of a sting they have a long, thin tail. This tail is for defence, as it can squirt acid from it, which smells like vinegar, (which is where "Vinegaroon" comes from I suppose).
Whip Scorpion palps have become powerful, crushing claws, to overcome their prey, eating insects but also small vertebrates too.
Like the Scorpion, the Whip Scorpion cares for her eggs and carries her many young on her back, and they live to around 3 to 4 years.