I find the earth element easy to use in the meta of magic attacks as it has a lot of monsters that benefit if you use Obsidian as your summoner.
White with all its armor buffing skills from monsters and summoners feels like using earth element magic attacks negates a lot of their advantages.
Even with a high HP and a negated armor advantage the enemy's tank quickly fall in the first round.
Using a flying tank with a magic attack helps in being able to in melee range and dodge a couple of attacks and getting some heals from the backline helped further that it never died from the repeated range attacks from the back.
Whatever the +2 armor skill advantage it would bring to other types of monsters was useless against magic attacks.
Thr first 3 positions quickly fell and range being unable to attack when in melee range spelled the end by round 3.