A few basics about the Machine Robo as shown in the series probably need clarifying. Bandai and/or Ashi don't seem to have laid down much in the way of rules which can lead to a lot of confusion when watching the series.

This is my attempt to straighten some of it out by answering a few questions that came into my head while watching the series and - I'd like to think - would be pondered by anyone else watching the thing.


HOW MANY OF EACH MACHINE ROBO TYPE ARE THERE?

Multiple Submarine RoboProbably the most baffling aspect of the series is the way the toy-based Machine Robo (i.e. the Battle and Jet Tribes) are actually utilised. Some - such as series leads Rod Drill, Blue Jet and Triple Jim - we only see one example of. Others - most notably Submarine Robo, twenty-odd of which are seen onscreen in their only appearance - are obviously widely used body types. Throwing things into the mix are the names used - some Machine Robo (such as Trim Sponsor, Vilion or Ren) are given individual names. Some are just referred to by their toy names (for example Bike Robo, Fire Robo or Apollo Robo - occasionally the 'Robo' bit is dropped, but not consistently).

Skyline Robo - dies twice, still makes the finaleIn between there are some strange grey areas that can cause confusion. Combat Buggy for example first appears as a named guest character and reappears for the Demonic Castle two-parter. Later on a Combat Buggy is seen onboard the Battle Base in several scenes - is it the same guy or someone different? There's nothing solid to say either way. Even more confusing are the characters who get fairly unambiguous deaths (such as Phantom Robo or Skyline Robo) and then turn up again later, yet are only ever seen one at a time. And then there's the likes of Supercar Robo, who is seen as a criminal in Bug Newman's gang and then as an elderly-sounding scientist.

In short there seem to be very few hard and fast rules set and it's best to judge on a case-by-case basis. For my part unless there's a solid reason to think otherwise I tend to assume all the actions of a Machine Robo are the actions of the same guy, for reasons of neatness if nothing else.


DO MACHINE ROBO HAVE GENDERS, RELATIONSHIPS AND FAMILIES?

Blue Jet romancing RuryYes, is the short version. Cross-Tribe relationships seem normal - Blue Jet (Jet Tribe) courts Rury (Cronos Tribe), Combat Buggy (Battle Tribe) gets with Melodia (Cronos Tribe), Tough Trailer (Battle Tribe) has a thing for Diondra (Gyandlar), Apollo Robo (Jet Tribe) fancies Leina (Cronos Tribe) and so on. Apart from Diondra, the only females seen are Cronos Tribe (that we know of, anyway - it's always possible that some of the non-speaking Battle and Jet Tribe characters are female) with the exception of Sara (who will get a paragraph to herself in a moment).

Young Stol childrenFamily units also exist, though solid information is scattered across the series. The Stol family are the most obvious example. While no mother is seen or mentioned Kirai is clearly the father and his three children Rom, Leina and Gardi are seen. The kids get bigger at some point after their arrival on Cronos and the implication is there that they grow - this sort of thing is complicated by Ashi largely treating the Cronos Tribe as humans up until the point they get torn apart and there are circuits everywhere; you could possibly argue that they simply get given 'adult' bodies at a certain age but that would probably fail Occam's Razor. Sure, metal beings that grow with age aren't especially scientific but Revenge of Cronos dabbles with a lot of stuff that is most easily described as 'magic'. Much the same conclusions can be drawn around whether Machine Robo reproduce sexually or build new robots and program them - on the one hand the latter is probably the most sensible explanation but it's not always a particularly sensible show; Combat Buggy is in a relationship with someone the size of his leg.

Baby Supercar Robo and Baby Skyline RoboOther siblings seen are the brothers Pro Truck Racer and Tough Trailer, but most family units shown are Cronos Tribe. There are a couple of exceptions - small, chibi-style versions of Supercar Robo, Skyline Robo and Battle Rock are seen as children on a couple of occasions, usually with dialogue making it obvious they're kids and not just midgets.

Sara of GurianThe most curious character from this point of view is Sara, resident of Gurian. She is the daughter of town chief Reni, a Bulldozer Robo, but outwardly resembles a Cronos Tribe female. However, she transforms into a scooter. What exactly this means - whether her mother is/was from the Cronos Tribe, whether she was just build this way by Reni and so on - is unclear but she's the exception to just about any rule you can come up with.


WHAT ARE THE ATTRIBUTES OF A MACHINE ROBO?

Beyond being metal robots it's difficult to tell. They all seem to be sentient beings with a full range of emotions, though there's absolutely no clue to the origins of the species in the cartoon. Most seem to have basically good personalities and the species doesn't seem particularly warlike, often being very passive and easily quelled by the Gyandlar invaders. Few seem to have natural fighting skills - the most formidable are generally those trained by offworlder Kirai Stol. Apart from some who turn into military vehicles they have no built-in weaponry, being reliant on rifles or swords. They are able to eat, drink and sleep - how much of this is actually necessary is unclear as these actions were generally played up for comedy value, being Rod Drill's favourite pastimes that no-one else seemed to bother with.

How big the Machine Robo actually are is open to conjecture as the entire series takes place on an alien planet with nothing that's definitely the same size as it is on our world. If Rom was, say, 6ft tall that would make the average Battle or Jet Tribe member only around 8-10ft tall. Taking, say, Skyline Robo as being in scale with us humans he'd be about 20ft tall, making Rom or Leina around 15-16ft. There isn't much cheating with mass shifting but toy size seems to play a bigger role in how big a character is than the size of their alternate mode - Shuttle Robo and Police Robo are roughly the same size in both modes despite one being a space shuttle and the other a police car; Pro Truck Racer towers over both as his toy was much larger even through he turns into a truck cab and should still be much smaller than a Shuttle. There is the odd exception (hello, Battleship Robo!) but it's the closest thing to a constant. Most Battle/Jet Tribe members can take a Cronos Tribe pilot but then any example that would really show this up as a scale problem - someone piloting Blackbird Robo, for example - is avoided, possibly intentionally; notably when they need a shuttle to go into space the larger Big Shuttle Robo (who is roughly the same size compared to Rom as a real Space Shuttle would be to a human) is pressed into action.


WHY DO THEY CHANGE INTO EARTH VEHICLES?

Good question. In Challenge of the Gobots the question was vaguely handwaved as it was hinted that Gobots had been to Earth in the past and had some ability to monitor the planet. The people of Cronos have no idea Earth even exists (it might not in this fictional universe) so it's impossible that the same is true.

One possible, if slightly fannish, explanation is offered by the dimensional gateways shown at the end of the series. The pre-Cronos mythos had the Machine Robo as dimensional travellers defending Earth, adapting local vehicle forms to help combat their Devil Invader enemies. If they've already travelled through one dimensional gateway it's possible they did so again ahead of this series, and simply kept their Earth disguises. Further support is provided by sequel series Battle Hackers which has selected Machine Robo emerge in another dimension again, retaining their vehicle forms but not their memories.

Or it could be because the toys turn into Earth vehicles.