My question is how did the animals turn into humanoid form 
the same way humans evolved from apes?
I was thinking that when the ‘apocalypse’ happend on 1st earth (our current earth), gene pools might have fused somehow.
Or, alternatievly… how did humanity evolve into a myriad of animal anthro species. Intentional genetic engineering? nuclear apocalyspe? In all of the preview images/info, we have yet to see any surviving humans like in the original show. (though they might still be there.) Both options are possible.
at the start
When Claudus was speaking of Thundera’s past, he said there was war among all animals. That the cats ended up on top and brought peace to their people. My guess is at one point every animal on third earth was an equal and all were at each others throats for the good lands. Only after the sword of Omens was born did the cats gain control of a choice chunk of land. Now, knowing how huge a planet is i highly doubt the rest of the earth is bleak and desolate, and likely the grudge is something like two species waring over the same plot of land each claiming they were there first. The cats won, walled themselves in and like Ba Sing Se became ignorant of what went on beyond their walls. It seems like generations have gone by since Thundercats went out of their grounds. Like normal cats territory is everything, so they do not have a huge trade system set up, and likely expect traders to come to them. Not seeing a need to leave the layer. They want the book of Omens, which is likely what holds the Thundercats code in it’s pages. Something that’s embedded in the souls of noble Thundercats, but obscured by time and spoils.
It comes as no surprise that after generations of fat and lazy, safe and healthy i’m better than all else attitudes, you get a type of ignorant racism like we saw in the first two episodes. Lion-O thinks outside the box, like in the original show, so it comes as no surprise that he’d question things most other Thundercats would take for granted. I have a feeling that the Thundercats are going to be met with prejudice much like what Drzzt Do’urden deals with in R.A Salvators books. That the world will see them as deadly bullies, savages, who would sooner cut their throats and take their things then extend a helping hand. But as it is Lion-O’s innate nature to help others in need, that view will change slowly as the show progress’. All my speculations of course. I look forward to seeing how it all develops.
Couldn’t be. Third Earth is very clearly not our planet as the premiere episode showed that it orbits a gas giant and has at least one moon.
Yeah this scene here pretty much contradicts the theory that Third Earth is our Earth in this version. Though the OS very definately strongly hinted they were the same (even so far as having a Globe with our continents.)
In the premiere, they seemed to have normal days and nights. I wonder how that works around a gas giant. Perhaps the gas giant can somehow explain a “dark side.” Perhaps half the planet is always in darkness?
or more probably the concept artists just thought this looked cool without thinking about things like that. lol
That would seem to be typical for Hollywood. Often in shows I’ve noticed they do thing thinking the viewers won’t pick up on or think about. Perhaps it wasn’t as big of an issue before the internet where people like to discuss episodes in depth.
Gas giant? Looks like Jupiter to me.
The cats rule over the animals just like big cats do in the real life wild. I mean if you think about it no land animal is more fierce or strong. When the apocalypse that (presumingly) mumm-ra caused happend, humanoid forms of earths animals arose from the ashes and started fighting over lands, naturaly big cats (thundercats) won.
Jupiter is a Gas Giant.
Astronomy 101! 
I do believe all the planets in our solar system beyond the asteroid belt are gas giants. Pretty sure that’s what I was taught. Which would be: Jupiter, Saturn, Uranus, and Neptune. Now if Pluto were still a planet, then it would be one planet beyond the asteroid belt that wasn’t a gas giant. Poor Pluto.
I like the change too, makes things more interesting and really, it’s a reasonable motivation for the lizard people.
Throwing out a crazy theory here… Could Jaga have been a crazy fundamentalist prepared to sacrifice Thundera for the good of the world?
I think it is Jaga who states in the intro, that the changes to come was necessary… He also ignores the visions that Lion-O is receiving even though he with most certainty know them to be a bad omen.
Has Jaga enough knowledge of the book of Omens to know that at least some of the Thundercats will survive to found a new dynasty based on understanding with the other races, and is prepared to sacrifice Thundera for the greater good.
He does have the streak of a fundamentalist as he sacrifices himself allow the future “messiah” to get away.
He is not very cheerful with his clerics either… “To the death”… not “To victory” or something that makes sense.
It is a far fetched theory but it would add a nice touch to Jaga being a devote cleric who puts the religion of “The book of Omens” above everything else.
I am really enjoying the ‘gray area’ between good and evil that this show is exploring, and yes, it would appear that the ruling class in Thundercats had grown elitist and arrogant and needed to be taken down a peg.
As for the fall of Thundera, the majority of their military appears broken and only one cleric remains but I’m going to assume the rest of population is somewhat intact unless Mumra and his co-horts want ‘power’ over a pile of rubble and corpses. Another assumption would be the lizards enslaving cats out of retribution and continued military build up, giving Lion-O someone to rescue when he returns with the book and runes to show down with Mumra.
I got the impression that we were listening to Jaga talk about events in the past. Jaga narrating past events. Kind of like at the beginning of Fellowship of the Rings with Galadriel. Could be wrong, but that’s the impression I got.