Yep, two Es.
_ _ E
_ _
_ E _ _ _ _ _
And I’ll say O.
Two Os as well:
_ _ E
O _
_ E _ _ _ _ O
Letters used: E, O
Guss the first word starts with a T, so I’ll ask for that one and maybe some more.
Yes! Two Ts. And I’m now realizing that this puzzle might not be as tricky as I thought it was…
T _ E
O _
_ E _ T _ _ O
Letters used: E, O, T
Any S’s?
One S.
T _ E
_ _ _ _ _ S
O _
_ E _ T _ _ O
Letters used: E, O, T, S
I’m sure I was expecting more than that . . . OK, any R’s then?
Let’s also see if there are any A’s
Two Rs, but not an A in sight.
T _ E
_ R _ _ _ _ _ _ _
_ _ _ _ _ S
O _
_ E R T _ _ O
Letters used: E, O, T, S, R, A
OK, I’ve got four of the words now. Let’s have the I’s. There’s at least three that I can think of, maybe more.
I have a feeling there are some Cs in there. 
The Crumbling Cliffs Of Vertigo?
The Crumbling Cliffs of Vertigo! You’re up, Liam. [emoji4]
I’d got as far as The (?) Cliffs Of Vertigo, and couldn’t think of the missing word - and miscounted the second word as having 8 letters rather than 9, but then it hit me - like a piece of that cliff crumbling above my head!
OK, let’s see . . .
Let’s start off with E
Good start. One in every word!
_ _ E _
_ E _ _ _
_ _ _ _ E _
And let’s follow with R
Just the one:
_ R E _
_ E _ _ _
_ _ _ _ E _
Used: E, R
Any N then?