1. The cassettes - Frenzy, Rumble, Ramhorn, Eject, all the others - are parasitical mechs.
a. They can drink energon, but it's not very efficient for them, and to properly refuel, they need a host.
b. Preferences are enemy mechs - Lazerbeak, Buzzsaw, seek out unwary Autobots, Steeljaw, Rewind, hunt down Decepticions
c. Femmes can't be utilized - something about their sparks is poison to parastical cassettes.
d. Carrier mechs (Tape Decks) are able to support more than one cassette at a time, with few negative side effects.
e. Soundwave and Blaster, don't have full sparks due to constantly being 'drained'
f. Tape Decks are fully matured parasitical mechs that don't need spark energy to sustain themselves.
g. Cassettes (Ratbat, Flipsides, Ravage, etc) can share the spark-energies drained from others with their hosts.
h. Cassette Players (Blaster, Soundwave), are immune to the spark drain
I. Being immune, they can support dozens of immature cassettes and those with only half-a-spark
II. Being immune, they are the preferred energy source of cassettes.
III. Because they are immune, they don't realize that their cassettes are a threat to their respective army's healt.
i. The cassettes are parasitical only under specific conditions - (not all the time, like once a vorn, or at random times, and rarely more than one or two at a time)
j. The cassettes aren't really Parasites - Megatron only thinks they are. Optimus knows they are aren't.
2. Mature Tape Decks have mental powers - like telepathy and empathy - that are enhanced when combined with the smaller, mobile mechs. (The more cassettes, the larger the cohort, the stronger their mental power and ability to influence/touch others)
3. Rewind, Lasserbeak, etc, are offshoots of city-mechs (like Typricon), - melded consciousness, melded spark to the largest known mecha, (extensions), yet separate – used as couriers and unbreakable lines of communication.
Eject, Buzzsaw, etc – can survive away/without being reabsorbed back into city-former sparks, but only if given room to dock with a combatable carrier.
Ergo, every sparked city has a minimum of one communication mech that doubled as a cassette carrier, who traded information across faction borders – when the city dies, often the cohort carrier and cassettes do too, (since A, tape decks are rare, B, few mecha are willing to siphon their own spark energies for strangers, C, carriers go insane without micros around)
4. Cassettes are extensions of a city-former.
Need morbile spark-carrier if to survive away from city-mech.
Only some can sustanin detached, unstable life forms – fewer still are willing to ‘dock’ them.
5. Cassettes – are future gestalts. (If they survive, and get sufficient fuel)