Well I need all the help I can get, meaning I need help from set bonuses
Believe it or not, but I can say that my set combination, especially Valhalla Knight's Breastplate. Can provide a longer survivability than the Beetle Shell.
Therefore, most other set bonusses at that tier aren't really that useful against Moon Lord:
- Turtle Armor's bonus is useless because almost all ML's attacks are projectile based.
- Shroomite requires you to stand still, which is the least recommended strategy to do so.
- Spectre healing is negated because of the Moon Bite Debuff.
- Spectre offence is not recommended because you've no control where the orbs fly at.
In terms of set bonus, you're likely only the best off with Beetle or Titanium. both are also depending if you can dodge enough attacks for the set bonus to charge it's defence/dodge.
As for the Valhalla Knight's breastplate, besides it gives almost the same defense as the beetle shell, it also gives of a great healing effect, which was otherwise a set bonus as well (for Crimson/Palladium armor). Meaning that if you dodge enough, you'll soon recover all the damage inflicted, effectively nullifying it.
So the healing effect of the breastplate technically is your set bonus.