Familiars
_____When a Magic Animal Familiar bonds with a magus, they loose their immortality and start to age as their magus does. They also loose the normal prohibition limiting learning abilities as long as their magus is involved (as a teacher, gaining Exposure from working together, Adventuring together, etcetera), but cannot achieve further Transformation (perhaps with assistance in the lab though). In abstract, Familiars may receive 20xp per year (or on average 5 per season) for Advancement/Development.
_____As the base default, a Familiar is a Magic Animal (possibly a Beast of Virtue), created as a Summer Character (360xp) with a Might of 10. A Spring Character (120xp) with a Might of 15 is also acceptable. More powerful and/or wiser familars are possible, but this requires a story or special Virtue/Flaw. A good example is a newly gauntleted maga with a Magic Animal Companion as a Minor Flaw. The animal, not yet a familiar yet potentially so, can e a Winter character with a Might of 10 or as an Autumn character (720xp) with a Might of 20.
_____Your Bond Score is determined by your Lab Total, which must equal or exceed the required Bond Level (Might + 25 + five times Size). The difference between these scores is your Bond Potential. This "space" can be enhanced with Bond Qualities, which requires a Season for each one and are similar in some regards to Magic Qualities. Minor Bond Qualities take up 5 points of space and Major ones require 15 points. In a way, you can view this as Retempering the Bond at a higher level.
[tab][/tab]This concept is not fully developed yet (from a rules perspective), and the advantage offered versus effort required is not that great. Just take note of what your Bond Potential is. It may become relevant at some future point.