I've used the walkthrough but can't seem to find the spot in the imperial arena where I should drop the assasin's note for the shadowscale to come see me. Could someone provide me with like a picture of where exactly it needs to be?

thanks

go to the place where you met ruin tail for the first time

by the statue when you first fast travel to the arena drop the note there and a shadow should appear

Garrus

I know, I've tried that. He just never appears.