While I understand what you are saying, Minette, I'm not entirely sure your solution would be better. I think we both agree that the Guardian's gas blast is really it's dominant defense mechanism. If you were to average the damage from gas blast over the course of a battle, you have to pick a number that is higher than the average heal rate of the members involved. This number, I think, would be roughly equal to the second gas blast. If it's much lower, then the ratio of damage received to damaged healed will be less than one, making the attack negligible.
Secondly, I've been in groups of where no one died from the inner guardian. It just takes a lot more preparation and a light tighter of a group. Armor has to be better enchanted, scouts have to have plenty of herbs, etc etc.
Third, remember that a multi-relic guardian will be significantly more powerful. People
should die in the raid attempt.
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(This comment assumes we're talking about the same raid.) If people don't die, than, IMO, the system is broken.
sleeper