Earthlock: Festival of Magic

Story related, cannot be missed.

PAT is the machine that Lady Lumia was talking about when you reunited with Olia. During the game, you'll eventually be in a warehouse where you will find this machine being stolen by a Great Wave Guard and Aderyn. Aderyn will activate the machine forcing you into Boss Fight.

List of Great Wave Guard, PAT and Aderyn's Attacks:

• Lance: Attacks one ally with a ranged piercing attack.
• Single Out: Inflicts Slow on one of your party members.
• Power Shot: Attacks one ally with a fire arrow that has a 25% chance of inflicting Burning. This move also has a 25% chance of inflicting Stunning, which will skip that ally's turn.
• Blinding Shot: Attacks one ally with an arrow that has a 25% chance of inflicting Blind.
• Flame Strike: Attacks all allies with an air blade of flames emitted from her bow that has a 25% chance of inflicting Burning.
• Confusing Shot: Attacks one ally with an arrow that has a 25% chance of inflicting Confused.

Boss Fight Strategy: Great Wave Guard, PAT and Aderyn

This battle isn't all that difficult especially if your Taika has a Predator S ready. Start the battle off by using Predator S into a Fire Breath S to inflict extreme damage on all three enemies, which also has a chance of inflicting Burning. Have Olia or Ive simply making basic attacks while only focusing on killing the Great Wave Guard or PAT first. If Ive has any Toxic Lances, you can use these to add Poison status against the human enemies. Additionally, if your Olia has Blood Shout, use it to inflict Bleed on the Great Wave Guard. Have Armon in Thief stance and use Gouge constantly on Aderyn because she's able to be inflicted with the Bleeding status for 3 turns. PAT doesn't do much against your party since he's in his defense stance. Have Gnart focus only on healing as necessary. When it's Taika's turn again, using her Predator S into a Quake S which should take out both PAT and the Great Wave Guard. The rest of the battle should be easy for you as Aderyn isn't that much of a threat by herself. Upon defeating her, you'll get the Defense Expertise Perk Talent and a cutscene will trigger after the battle. During this cutscene, PAT will join your party, unlocking the trophy.