Earth is one of my favourite elements as it comes with 2 pretty nice tanks: Nectar Queen and the Unicorn Mustang
Both are without armour but they 10 HP count compensates for it.

The unicorn has much higher initiative and has some resilience to magic with the void ability.

The queen has one extra melee strength and can fly to evade attacks. However if you are looking for evasion I would rather recommend the unicorn as its high initiative gives a decent evasion chance.

What setting are better for the unicorn

I would recommend the Unicorn for “broken arrow” and “armoured up” settings. Both of those setting encourage your opponent to used monster with magic attack, which increase the value of the void ability

Also the unicorn is slightly cheaper than the queen, so in a game with low mana cap it might be wiser to used it as a tank.

What setting are better for the queen

“True aim” and “reverse speed” will make the unicorn lose its speed advantage. Therefore I will recommend the Queen in both setup.

“Earthquake” is obviously better for the queen as it can fly. however if the mana cap is sufficient I recommend to put the unicorn in front line with the queen in backup behind. This will protect your queen for few turns.

Example of battle

Here is an example of battle with a setup I haven’t yet mention: Melee Mayhem. This is a perfect opportunity to bring in all my good earth melee monsters.

The setup

Unprotected
Melee Mayhem.
Mana cap 46

The line-up

Summoner: Drake of Arnak lvl 2

Orc Sergeant lvl 2: This monster doesn’t have much attack strong but it has a reasonable HP count so it can by time for the other monster to bring havoc on my enemy.
Unicorn Mustang lvl 1
Rexxie lev 3
Nectar Queen lvl 3
Wood Nymph lvl 3: to heal a bit my tanks.
Prismatic Energy lvl 1: it is the long range monster with the most health at my disposal so it is perfect to protect my tail

The outcome

This was the initial line up:

My enemy had an attack strength of 3 long range, 2 madgic and 5 melee attack. So a total strength of 10
My melee monster alone had a strength og 13 :)

The superior fire power allowed me to win with only my Orc sergeant passing away: