Armors now have leans or an affinity toward offensive or defensive stats. offensive leans increase damage dealt and taken while defensive armors do the exact opposite.
As a rule it is best to go as heavily into the lean as possible preferring fully offensive over mid-offensive as an example.
Neutral armors are the baseline as a comparison for armor leans. They have no special quirks toward damage or defense being a middle ground that is rarely used.
Offensive leans are the preferred armor type for a majority of players. They increase both the damage dealt and taken in order to allow a quicker playstyle which promotes a "Kill him before he kills me" mentality.
Due to this mentality and playstyle, fully offensive is greatly preferred due to the damage multiplier on the armor being larger while damage taken is largely ignored when players can kill monsters without ever being attacked.
A great list of Offensive armors and a playstyle guide for offensive builds can be found at this link below:
Defensive armors are used by players who prefer to improve efficiency turn by turn rather than increase efficiency in times/turns spent per fight.
Players accomplish this by using mostly Fully Defensive armors along side 100 proc weapons to only receive 80% of the damage taken while dealing damage that can ignore the armor lean's offensive weakness.
Because defensive armors are used with weapons which ignore their damage dealt, Mid-Defensive armors are never better than their Fully Defensive counterparts.
A great list of Defensive armors and a playstyle guide for offensive builds can be found at this link below:
This is a mostly-defunct armor type which decreases damage dealt and increases damage taken in order to boost a mages spells in some way.
You may run into older armors using this system, but they are rarely worth using.
Pre-Lean Armors are armors that had offensive or defensive properties before the Lean system was fully implemented.
These armors typically have a fully offensive boost to damage or a fully defensive boost to defense while not receiving the associated downside with those specific armor types.
Pre-lean armors can be recognized easily because they have no armor indicator in-game. However, this prevents players from easily recognizing whether the armor is Standard, Offensive, or Defensive.