Designed Opposition

People keep asking what can possibly face off against an Elemental. The unique thing about Elementals compared to other combat units is that their power scales up massively as they develop in skill, so what is appropriate to counter one is always changing. For any Elemental Tier2 or below (no fully solidified shielding) this bio neural mech will be an even if not a lethal opponent.

A Biological Synthetic, Neurologically Controlled mech, or Bio Neural mech. Using highly articulated limbs of synthetic muscle controlled by a connected pilot, it can move around much more nimbly than a conventional combat mech.
This model has been specifically designed to combat opposing shielded units, most notably Elementals. It comes standard with a battery of shield generators and it's large reactor gives them great power considering their often low tier of development (dependant on the pilot).
The back unit can be swapped out for different weapons and equipment. Shown load out is 2 Railguns, 4 missile pods, and arm mounted pile launchers. Hand held weapons are also commonly used.
Dense ballistic projectiles have the highest success against low tier Elementals. Against experienced foes counter shield generating rounds may be used, but these are costly as they consume valuable shield generator material. Controlled frangible or airburst rounds are also effective if they can penetrate all shield layers before breaking up. Group tactics also greatly increase success by crossing vectors of fire, making it harder for a target to evade.
This units main value is in it's survivability though. When an Elemental encounters a foe that it cannot easily kill it's momentum is suppressed, unable to freely move around the battlefield to pick targets. Occupying the Elemental in a prolonged engagement keeps the heat off of other forces.