Can anyone identify this monster?

[ZaZathecat]

Saw this beast in the park today. It's about 8cm from end to end including feelers. Some sort of hornet maybe? Does anyone know what it is?

It may be a wood wasp.

They’re harmless, by the way; don’t have nightmares!

Thanks Yea Sayer. Isn't that a massive sting in its tail then? Or maybe it pretends to have a sting to fool predators?

No, it’s an ovipositor, to lay it’s eggs deep inside wood

Oh yes have just googled wood wasp and I think you're right!