If you properly Special Summoned him first, and he is then destroyed, you can special summon him back from the graveyard with cards like Monster Reborn.
You do not need to remove another Light and Dark monster to do this, and just as important, you cannot remove a Light and Dark monster to special summon him from the graveyard, he can only be summoned from hand by doing that.
Yes, you can special summon it from the graveyard, but only if;
A - It was properly special summoned first before it went to the graveyard, and,
B - You are using an external effect to summon it like Monster Reborn or Call of the Haunted. You may not use Chaos Sorcerer's inherent special summoning method of removing a Light and a Dark monster from the graveyard, this can only be done when it is in your hand.
A monster's special summon method, unless specifically stated otherwise, is from hand only. You can remove a Light and Dark monster to summon Chaos Sorcerer only while it is in hand.Plaguespreader Zombie is an example of a monster who can special summon itself from another zone, the graveyard in his case.
Chaos Sorcerer must be initially summoned from hand. You cannot use his own special summon effect from any other location, like the graveyard. However, if he is properly special summoned by this method, and then destroyed, you are allowed to special summon him from the graveyard using cards like Monster Reborn. Monsters who say "can only be special summoned by..." all work like this, but ones who say "cannot be special summoned except by.." can't use any other method but their own. Lastly, if he's in the graveyard but was not properly summoned (like, his summon was negated, or he was simply discarded there) you can't use Monster Reborn on him.
No, unless specifically stated otherwise on the card, a monster's special summon requires it to be summoned from your hand, or in the case of Synchro and XYZ monsters, from the Extra Deck.Plaguespreader Zombie can special summon itself from the graveyard because it says it can. But you cannot use for example, the special summon requirements on Chaos Sorcerer, or an XYZ monster, while they are in the graveyard.
Yes as long as you have 4 lightsworn monsters in your graveyard with different names. Remember that Judgment Dragon's summon does not require you to remove the monsters from the graveyard (unlike Chaos Sorcerer), so if the condition was correct for one Judgment Dragon, it's still correct for another.
The 'Chaos' monsters - Chaos Sorcerer, Chaos Emperor Dragon Envoy of the End, and Black Luster Soldier Envoy of the Beginning must be special summoned initially from hand by removing from play 1 light and 1 dark monster in you graveyard from play. Once you do this, after the monster is destroyed and goes to the graveyard, you can then resummon it using cards like Monster Reborn.
No. Unless specifically stated otherwise, a card's special summon text is to summon it from the hand only. Chaos Emperor Dragon requires the owner to remove one Light and one Dark monster to summon it from his hand, but it cannot be done while it is in the graveyard, and especially, the opponent cannot do it.
Initially, Chaos Sorcerer must be special summoned from hand by following the text on the card. It cannot be special summoned from hand though by any other effect, like that of A Hero Emerges - it can only summon itself using its own method.
Nope sorry. A monster's own special summoning method always refers to when it is in the hand, unless specifically stated otherwise. So you can't let a Chaos Sorcerer summon itself from the graveyard, but Plaguespreader Zombie can.
Stardust Dragon / Assault Mode cannot be special summoned 'except' by its own effect, or Assault Mode Activate. You are allowed to use Monster Reborn on cards like Chaos Sorcerer, who says it can 'only' be special summoned by a specific way - as long as you do summon it properly this way before it goes to the graveyard. But with the 'except' monsters, that's the only way it can be summoned. You cannot revive it from the graveyard, even if you properly summoned it initially.
Yes. Summoning Chaos Sorcerer is not an activation unlike the Triggered effects of Gorz or Battle Fader. It does not use the chain, just like Normal Summons. So Light and Darkness Dragon has no interaction with it.
Removing a Light and Dark monster can only special summon a Chaos Emperor Dragon from your own hand. When it's anywhere else, you can't remove another Light and Dark to summon it. If you summoned it properly, you can resummon it with Monster Reborn though.
Solemn Judgment can negate summons that don't use the chain, by waiting until the monster is placed on the field, then negating the summon before it counts as being successful. When a summon occurs on the resolution of an activated effect, the summon is automatically successful when the effect resolves - but Solemn Judgment can chain to that activation and prevent the summon by stopping the effect resolution. So, if you Normal Summon, Synchro Summon, or perform a special summon that does not use the chain, such as Chaos Sorcerer, you can negate the summon as per the first bit above. If you special summon on resolution of an activated effect, such as Monster Reborn or Call of the Haunted, Solemn Judgment can chain to these activations and negate them. No resolution means no summon. But, note that Solemn Judgment can only chain to the activation of Spell or Trap cards. If the special summon occurs on the resolution of an activated monster effect, Solemn Judgment can't stop it. It can't chain to it, and as above, the summon is successful when the effect resolves. So that is why Solemn Judgment can't do anything against the triggered effect of Gorz the Emissary of Darkness, but is able to stop special summons that aren't by resolution, such as Chaos Sorcerer.