Mutation requires two Bacteria of equal level and always gives one Bacteria of a higher level as a reward. The rarity of the mutated Bacteria is the same as the rarity of the used Bacteria. If they are of different rarities, the mutated Bacteria will have a random rarity in the same range, so it is not possible to obtain a higher rarity Bacteria through mutation.
Mutation is instantaneous and it requires no Scientists. However, after it is complete, the player has to clean the lab before it can be again used for mutations.
When calculating the mutation results, the effects of Bacteria A and Bacteria B play an important role.
Mutating Bacteria with similar effects gives a better chance to obtain a good result.
Mutation results are calculated by taking the average values of Bacteria A and Bacteria B, so Bacteria with better effects usually give better results.
Even though higher level Bacteria generally have better effect, it is possible to mutate a Bacteria with weaker bonuses, especially if A and B are of different rarities.
In most cases, Bacteria C will have the effects as either Bacteria A or Bacteria B. The exception is when C has more stats than A and B individually.
The name of C is random and does not depend on Bacteria A and B.