Here is the full list of all 12 Zippy the Circle Challenge (Level 11C, Level 12C, and Level 13C) trophies - there are 11 gold and 1 platinum.
Great job! You got all the trophies! Congratulations!
Complete Level 11
Complete Level 11 with the timer lower than 400
Complete Level 11 with the timer lower than 300
Get the medal for Level 11
Complete Level 12
Activate a switch in Level 12
Get the medal for Level 12
Complete Level 13
Complete Level 13 with the timer lower than 300
Complete Level 13 with the timer lower than 200
Get the medal for Level 13