Here is the full list of all 37 Magus trophies - there are 26 bronze, 5 silver, 5 gold and 1 platinum.
Obtain all trophies.
Obtain 500 Items.
Kill 100 Obsidian Guard.
Obtain 100 Health Potions.
Kill 100 Titans.
Kill 100 Undead.
Kill 100 Unicorns.
Use a Chroma-Skill for the first time.
Max out the levels of all the Blue Magic skills.
Max out the levels of all the Red Magic skills.
Max out the levels of all the Green Magic skills.
Defeat the Daemon Queen.
Reach level thirty.
Kill 100 Shai Soldiers.
Defeat the King.
Complete Azure Cove map.
Kill 1000 Enemies.
Kill 100 Dragonmen.
Equip a Rune for the first time.
Have the titan runemaster Vallos join your cause.
Complete Desert map.
Reach level twenty.
Extract Item attributes to a Scroll.
Have Usoph the Unicorn Elder join your cause.
Complete Mines map.
Complete Burial Grounds map.
Reach level ten.
Kill 100 Skeletons.
Unlock the "Raise Dead" skill.
Enter the Tower of the Gods.
Kill General Tiel and complete the Island map.
Kill 100 Kingdom Soldiers.
Add a Gem to an Item.
Kill Captian Rivers and complete the Dungeon map.
Kill Purifier Brooks.
Absorb the color from a power stone.
Have Kinna join your party.