Is there an official position on which order relics activate first?

EX: If Jasatur mask hits Oblation trap, does the attacker lose stamina from the trap before gaining stamina from his mask, or the other way around?

I don't know if there might be a mechanic in the game that says "masks go first, then traps, then xxxx, etc." or not. Or perhaps it's "attack's relic activates first, then defenders". ?

I have not studied it, but my guess is it is attacker's relic first.
Jakugan Sword often kills a monster before the Healing Mask can kick in.

Yes, Ekto is correct - attack relic triggers first then defence relics if still alive! So whilst I haven't encountered that situation, I would expect the mask to add stamina BEFORE the Oblation Trap removes it....

When I have the chance, I'd try that myself and see