Ruling Question #2

This time I will ask the question before starting the article. This is just for the purposes of checking your background knowledge in the game.

Both players have a face-up "Sangan" and a face-up "Light and Darkness Dragon". As the turn player, you attack your opponents "Sangan" with your "Sangan". What are the chain links of this situation? (No results are needed, just simply tell which monster is placed where in the chain.)

Hint: http://yugioh.wikia.com/wiki/Simultaneous_Effects_Go_On_Chain

[21:30:02] [5.121.202.203 - {AE's Dragon Tamer}Zerglot]
if sangan atks sangan then you have two chains going at the same time with the same links of: Cl1 sangan, Cl2 Ladd(opponent), Cl3 Ladd(yours), and continueing like that between the two Ladd

To answer this question...

Both LaDD's trigger to the Sangan's effects. Thus when placed on the link, the Sangan's come first with LaDD following. If you read the articles and links, you'll understand why the link is the following way:

Chain Link 1 - Your Sangan
Chain Link 2 - Opponent's Sangan
Chain Link 3 - Your LaDD
Chain Link 4 - Opponent's LaDD

When this chain resolves, the first LaDD, negates his own Sangan. Thus, its attack and defense becomes 2300/1900. When its time for your LaDD to negate the opponent's Sangan, the effect is already negated, meaning that your LaDD's effect fizzles out, so it loses no attack or defense. With Both LaDD having been used, your Sangan is the last in the chain and it gets it effect without worry.