Simultaneous Effects Go On Chain

**Simultaneous Effect Go On Chain** (Japanese: 複（ふく）数（すう）の効（こう）果（か）が同（どう）時（じ）に発（はつ）動（どう）する場（ば）合（あい）, *Fukusū no Kōka ga Dōji ni Hatsudō suru Bāi*), commonly abbreviated as **SEGOC**, is a process used to deal with multiple Trigger and/or Trigger-like Effects meeting their activation timing at the same time. If this occurs, all of the Trigger and Trigger-like Effects that are activated are placed on a Chain. For example, if "Mystic Tomato" attacks and destroys another "Mystic Tomato" by battle, both of their Trigger Effects meet their activation timings at the same time.

This does not apply to effects that activate "*During the […] Phase…*" or "*At the end of the […] Phase…*", such as "Gladiator Beast" monsters. Instead, each effect activates as Chain Link 1 of its own Chain.

If a Trigger or Trigger-like Effect meets its activation timing during the activation or resolution of a Chain, its effect cannot be activated until that Chain has fully resolved. If that effect did not miss the timing, it starts a new Chain immediately after the previous Chain fully resolves. If multiple Trigger and/or Trigger-like Effects do so, they all form a Chain using the "SEGOC" rules.

## Order

Trigger and Trigger-like Effects that would be activated at the same time are activated in the following order:

1. Turn player's mandatory effects
2. Non-turn player's mandatory effects
3. Turn player's optional effects
4. Non-turn player's optional effects

If multiple effects fall into the same category, the player that activates them chooses the order in which they are activated.

## Examples

 File:Sangan-YS17-EN-C-1E.png
Example 1
Each player control a copy of "Sangan" and "Peten the Dark Clown". The turn player activates "Dark Hole" to simultaneously destroy all of those monsters, so all four monsters' effects would activate at the same time.
* The turn player's only mandatory effect is the effect of their "Sangan", so it becomes Chain Link 1.
* The non-turn player's only mandatory effect is the effect of their "Sangan", so it becomes Chain Link 2.
* The turn player's only optional effect is the effect of their "Peten the Dark Clown", so it would become Chain Link 3 if they choose to activate it.
* The non-turn player's only optional effect is the effect of their "Peten the Dark Clown", so it would become Chain Link 4 if they choose to activate it.

Afterwards, players can add fast effects to the Chain normally.
If a player controls two effects in the same category (for example, the turn player controls two mandatory effects), then that player decides to order to activate them in.

Example 2
The turn player controls "Sangan" and "Witch of the Black Forest". The non-turn player controls "Dandylion". The turn player activates "Dark Hole" to simultaneously destroy all of those monsters, so all three monsters' effects would activate at the same time.
* The turn player's mandatory effects are the effects of their "Sangan" and "Witch of the Black Forest". These effects will be Chain Links 1 and 2, the turn player deciding the order in which they activate.
* The non-turn player's only mandatory effect is the effect of their "Dandylion", so it becomes Chain Link 3.
* The turn player has no optional effects, so none are added.
* The non-turn player has no optional effects, so none are added.

Afterwards, players can add fast effects to the Chain normally.
Even if one effect meets its activation requirements strictly after another effect, if they are in the same category they can be activated in any order.

Example 3
The turn player controls "Sangan". If the turn player Tribute Summons "Zaborg the Thunder Monarch" by Tributing "Sangan", then both monsters' effects activate at the same time.
* The turn player's mandatory effects are the effects of "Sangan" and "Zaborg the Thunder Monarch". These effects will be Chain Links 1 and 2, the turn player decides the order in which they activate (even though "Sangan" was sent to the Graveyard strictly before "Zaborg the Thunder Monarch" was Tribute Summoned).
* The non-turn player has no mandatory effects, so none are added.
* The turn player has no optional effects, so none are added.
* The non-turn player has no optional effects, so none are added.

Afterwards, players can add fast effects to the Chain normally.
## Limitation

Each player can only activate 1 Trigger Effect of a monster that could Special Summon the monster itself from the hand per Chain.

Example 1: Even if the player has both "Battle Fader" and "Ogre of the Scarlet Sorrow" in their hand when their opponent declares their second direct attack during a given turn, they can only activate the effect of one of those cards.
Example 2: When a face-up Beast-Type monster the player controls is destroyed and sent to the Graveyard, even if there are multiple copies of "Green Baboon, Defender of the Forest" in their hand and/or Graveyard, they can only activate the effect of one of them. This applies even if all copies are in the Graveyard.
## References

1. ↑ 1.0 1.1 1.2 Template:Cite book
2. ↑ Template:Cite book
3. ↑ Template:Cite book
4. ↑ Template:Database link: When a Beast-Type monster is destroyed, can you Special Summon multiple "Green Baboon, Defender of the Forest"?