A common question that I see is this: Who would win, Catastor or Mole? Well, the answer may surprise you. The simplicity of the explanation may be even more surprising.
Grand Mole wins every time. Why? Because he’s optional.
This might not make a lot of sense at first, so let’s establish a foundation for the answer. We’ll start by looking at the stats of each card.
Ally of Justice Catastor
At the start of the Damage Step, if this card battles a non-DARK monster: Destroy that monster immediately (without damage calculation).
Neo-Spacian Grand Mole
At the start of the Damage Step, if this card battles an opponent’s monster: You can return both monsters to the hand (without damage calculation).
Right off the bat we see that both of these cards activate at the same time, which is at the start of the Damage Step. But there’s a fundamental difference between the two effects. No, it’s not that one destroys and the other returns monsters to the hand. The fundamental difference I’m talking about is that one is optional and the other is not.
So, why is that important? Well, when two or more Trigger Effects or Trigger-like effects activate at the same time, they form a Chain. There are two key factors that determine which cards go on which Chain Link: Whose turn it is and which effects are optional or mandatory. This is a special rule commonly known as SEGOC (Simultaneous Effects Go On the Chain).
The order goes like this.
- Turn Player’s mandatory effect(s)
- Opponent’s mandatory effect(s)
- Turn Player’s optional effect(s)
- Opponent’s optional effect(s)
Remember that Catastor is mandatory, while Grand mole is optional. This means that it doesn’t matter who controls which card, or whose turn it is. Catastor will always go on Chain Link 1 because it is mandatory.
So, how does this mean that Grand Mole wins over Catastor? It’s simple: Chains resolve backwards. When it’s time to resolve a Chain- that is, to actually perform all the effects on that Chain- you start with the last Chain Link and work your way back to the first one. Since Grand Mole will always be Chain Link 2, Grand Mole will always resolve first, bouncing himself and Catastor off the field before Catastor (sitting on Chain Link 1) can destroy him.
So basically, Catastor and Mole both try to get in line. Catastor, being mandatory, is shoves his way to the head of the line. Grand Mole, being optional, just shrugs and gets behind him. And then Catastor learns that the players are going to start from the BACK of the line instead of the front, making it a very sad machine.
The SEGOC rules can be applied in a wide variety of situations. Try to use them to your advantage whenever possible! More information about SEGOC can be found here on the Yu-Gi-Oh! wiki.