Step 1: make a taming pen.
Step 2: put a lvl 80+ baby wyvern into the pen. Knock it out if you want to and lower its health down to almost 0.
Step 3: Drop troodon inside while its eyes are glowing.
Step 4: Enjoy your tamed troodon
At lvl 72 with flak armor on, a lvl 5 Troodon knocked me out with one attack at night. Last thing I saw was those glowing eyes before passing out. My Guess is that they attack vital organs. Luckily my Doedicarus was up for a game of baseball and launched that little devil out into the stands.