I used to play this one on Gaia!

Player 1 - POSTS A TABOO LETTER
Player 2 - POSTS A WORD WITHOUT THE TABOO LETTER, -and- A NEW LETTER
Player 3 - POSTS A WORD WITHOUT THE TABOO LETTER, -and- A NEW LETTER
And so on and so forth.

Let's start wiiiith:
TABOO LETTER = L

Vixen 

I

terror, r

amethyst, t

amber, a

tooth, t

Reference

i

estate, E

North, i

West , e 

North, T

happy, A

smoke, e

instinct, n

restful, T

house, u

horse, g

Word: Books

Letter: K

monster, R

mouse, I

bread, R