- The first sentence of the text is a condition, not an effect.
- The effect to prevent a Synchro Monster from being destroyed by battle and the ATK and DEF reduction are part of the same effect resolution. They do not start a Chain.
- Trust Guardian’s effect is mandatory. It protects the Synchro Monster even if it can’t lose 400 ATK and DEF. The ATK and DEF will remain reduced for as long as the Synchro Monster is face-up on the field.
- If a Synchro Monster winds up being Synchro Summoned using multiple Trust Guardian’s, it only loses 400 ATK and DEF each time it would be destroyed by battle.
- The text "This card cannot be used as Synchro Material Monster except for the Synchro Summon of a Level 7 or higher Synchro Monster." of "Trust Guardian" is not treated as an effect of an Effect Monster.
- The effect of "Trust Guardian" which decreases the ATK/DEF of the Synchro Monster is resolved as part of the effect which prevents the monster from being destroyed by battle. It does not start a Chain Link.
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