Muramasa Sentiment

The Muramasa Sentiment (村正の思念, Muramasa no Shinen) is a secret boss featured in Kingdom Hearts: Arcana. It is the imprint of Muramasa's existence left behind as a challenge for Flintlass.

Requirements
Muramasa's Sentiment Portal can be found in the Underground Cavern where Head Captain Yamamoto placed himself in an unconscious state after Muramasa initiated the Zanpakutō rebellion. The Portal will lead to the area in Karakura Town where Kōga Kuchiki was sealed for several hundred years. This is only available in Flintlass's story.

Strategy
The Sentiment begins the fight by firing a barrage of Bala in Flintlass's direction. Flash Step in a different direction to avoid it, then close in to get a few hits before it slashes six times in succession and fires Bala again. It will repeat this process until it has lost 2000 HP, at which it will increase its slashing combo to eighteen and fire short bursts of Bala in between the slashes. Get close enough to hit it and stall the slashing combo. By the time it reaches 1000 HP, it becomes the most deadly. The Sentiment will use high-speed slashing combos, coupled with its strongest attack; a purple Cero as large as itself. The range for the Cero is quite wide and is fired quickly, so Flash Step to an area above the Sentiment to avoid it before driving through a successive numbers of slashes, as it is open to attack at this moment.