I noticed that during the first fight when I just held down 'block', I would block attacks and the game would just say BLOCK. However, at one moment I let go of the block button to do an attack, but I noticed my opponent was attacking as well, so I pressed block again. The game then said PERFECT BLOCK.
I have been unable to repeat this after that, but my guess is it's something to do with timing. If so: how should I time my block move? If not: what does it depend on?
These quality levels are based on timing, and they are very unforgiving. Your action must occur very close to the moment the enemy would hit you. Note that timing applies to parry and dodge as well as block. There are actually three levels: normal, great, and perfect.
Unlike a normal block, a perfect block causes your shield to lose no durability. Getting a perfect as the last in a series also stuns the enemy slightly longer. When this happens, you'll see "Perfect Block Break". Additionally, they are sometimes requirements for a bonus (e.g. Perform X perfect blocks).
