One way to increase the effectiveness of your Familiars is through Evolution. Evolution allows you to combine two Familiars of the same evolutionary line to increase the stats, and rarity of a Familiar. Evolving a 1* Familiar two or more times will change the Familiar's rarity, and sometimes, its skill. See also Growth & Experience.
The familiar used as raw material in an evolution is called the "seed." Once used, the seed is removed from your familiars. Only one seed may be chosen in each evolution.The new evolved familiar will inherit 5% of the stats (including empower bonuses) for non-max level seeds and 10% (including empower bonuses) from max-level seeds.
The base Familiar to be evolved. The Spawn absorbs 5% of the Seed's stats (unless the seed is at max level in which case the Spawn absorbs 10%). The Resulting Familiar will have increased stats (including empowered bonuses), a new look, name, and sometimes skill.
When Sir Gareth goes form UC* to UC** he Recieved a bonus of 322 from the evolution and a bonus of 203 from a change in star level.
This bonus can be negative. When Sir Gareth goes form UC** to UC*** he dosen't get all his points. Note the addition of 332 to 3712 should be 4142. However the level cap for this Unit is 3932. So the bonus is efectivly -102. However If the unit was at lvl 49 then the resultant unit would be 3712 + 3218 * 5% = 3873 well under the cap. So even though the bonus may be negative it cannot be skiped for a PE.
When Sir Gareth goes form UC*** to R* he recieved a bonus of 322 from the evolution and a bonus of 588 from a change in rarety.