Whenever I use a transformation style I basically get swarmed and cut down within seconds. Usualyl the time it takes the bright flash that fills the whole screen to go away.

It's seems you transform to wrong creature. Don't transform to demon when your opponents with weapon, be spirit instead. Transform to demon when your enemies are magicians and martial artists.

General rule of this game seems to be later styles are better than earlier styles.

transformations styles toad demon is awful... horse deamon is okay personally i'd prefer standard fire magic, Jade golem is gaming breakingly good! massive damage, no damage from support styles you max it with a chi focused character and your enemies are just dead.

When i play through this game i usually max out a martial style just horde the skill points