Spell Speed:
* Spell Speed 1 (Slowest): Effects that activate when a specific event happens, like a monster being summoned.
* Spell Speed 2: Effects that can activate in response to another effect (usually Spell Speed 1) and can chain.
* Spell Speed 3: Effects that activate immediately, usually during the opponent's turn, and can also chain.
* Spell Speed 4 (Fastest): Effects that are continuous and always active, like some monster abilities.
Chaining:
* Chaining allows players to activate effects in response to other effects.
* To Chain, a card's effect needs to be activated in response to another card's effect.
* Spell Speed determines which effects can be activated in response to others.
The Rule:
A card with a higher or equal Spell Speed to the card its effect is being activated in response to can be chained.
However, there are more conditions:
* The card's effect needs to be specifically activated in response to the other card's effect (usually the effect will have specific wording like "in response to" or "when an effect is activated").
* The effect's activation timing must be correct (e.g., a card with Spell Speed 2 cannot be chained to a card with Spell Speed 4).
* There might be other restrictions on the card itself (e.g., it might only be able to be activated during certain phases or in response to specific types of effects).
Example:
* Your opponent activates a card with Spell Speed 1: "Summon a monster from your hand."
* You have a card with Spell Speed 2: "Negate the Summoning of a monster."
* You can chain your Spell Speed 2 card to your opponent's Spell Speed 1 card because it has a higher Spell Speed and its effect is specifically activated in response to the summoning of a monster.
In summary:
While Spell Speed is important for chaining, other factors like effect timing, restrictions, and specific wording also play a crucial role.