Activating this trainer:
Press F1 at main menu.
Listen for 'Trainer Activated'.
Press desired hotkey. All hotkeys can be changed on the trainer.
NumPad1: Infinite Mana
NumPad2: Infinite HQ Durability
NumPad3: Low Enemy Mana
NumPad4: Low Enemy HQ Durability
NumPad5: Change Money By 50
NumPad6: Change Ruby By 50
NumPad7: Instant First Crush Tension Gauge
NumPad8: Infinite Time On First Crush
Money/Ruby: On map click visit your HQ. Then press hotkey or make your changes. You must leave and enter the HQ again to see it has changed.
Unlock more trainer options including updates from here - Monster Monpiece Trainer