Trio don are tamed by letting them earn combat experience by killing your tamed. It is recommended to feed them gigas, wyverns, spinos, rex, megalosaurus, broncos, gigantos, allo/carno/quetzal/therizino as these creatures give the most experience and tame the troodon faster.

Things to remember:

The creature MUST be on neutral or aggressive, but can be weakened or knocked out

Babies count towards taming despite not fighting

Troodon need around 1000 experience to be tamed, REGARDLESS OF LEVEL

Multiple troodon can be tamed with one kill

Troodon don't need to be sturdily attacking a target, you can bait them into killing it (if feeding larger creatures)

To find out how much experience your tame will give, use this formula:

BaseXP x (1+(level-1)x0.1)

Base XP for creatures can be found on wiki.

More Troodon Taming & KO Tips