Fate/Extra (Collector's Edition) Hints & Cheats

Saber's skill, Artillery Applause can be upgraded by using around 100-200 items during your run through the arena. After you used enough items you'd be able to speak with saber in your private room. If eligible, she'll be talking about wasteful spending and you'd get the confirmation that Artillery Applause have been upgraded to Thunderous Applause. It will cost 60mp instead of 40mp.

These can Be Unlocked on Chapter 5, before the boss battle with Assassin

After the 7th week on your 2nd playthrough, If you finished all of Taiga's request, she will give you a message that the arena is dangerous. There you will find a Special Boss fight at the end of the floor.

To upgrade Caster's Mantra: Bestial Sky to Merciful Sky, you must kill 5 of the Nephilim enemies throughout the game. Afterwards, you can initiate a conversation in your Private Room which will then upgrade Bestial Sky to Merciful Sky. Merciful Sky increases the next spell's power more than Bestial Sky. It also increases the MP cost from 30 to 60.