[Meltyred]

Originally Posted by Tusjecht

For Level 5, Crow chose an upgrade leveraging more on his colour of Silver, rather than his flight ability: Optical Conduction. The circumstances of why he did that is a spoiler for V11 and V12.

Optical Conduction wasn't a level up choice, it was a skill he learnt from

Spoiler for Spoilers:

training aka getting shot by lasers a ton(courtsey of Scarlet rain) until he met choco, who then blah blah stuff happened, he reflected laser from a enemy to save the day, learnt the skill. It was a bonus from external stimuli. For example Sky raker has a "Booster jump" skill, that was learnt while she was learning how to use her armament. (Long time since I read the actual vol, specifics not clear)
The best example would be Silver Crow learning to fly, he learnt it at the spur of the moment, despite not even leveling up at the time.