Isomer EX difficulty is a huge step up from normal, and will generally require substantially stronger ARSMG and RFHG echelons with good equipment.

Isomer Ranking accepts up to 10 echelons, so players trying to minmax their score should craft equipment to outfit as many viable echelons as their armory allow them to deploy. Players are highly recommended to also prepare multiple RFHG with high accuracy on top of properly enhancing their HOC units, as highly armored units with nonzero Evasion begin to show up in the Ranking Stage.

To field a bare minimum of 4 echelons, this bumps the 5★ Equipment recommendations up to:

Optical Sight (crit scope) x8+

(crit scope) x8+ PEQ x4+

x4+ HV Ammo x4+

x4+ AP Ammo x4+

x4+ Camouflage Cape x4+ Now required as there are hard DPS checks. 4★ is sufficient but should preferably be enhanced.

x4+

Having more equipment is very strongly recommended (enough for 4-5 ARSMG teams and 5-6 RFHG teams) as increasing the number of viable combat echelons deployed in ranking helps tremendously with map control and AP/turn.

You'll also need a greater number of HGs to fill out the echelons, since their buffs become more important. Thankfully, HG recipes are cheap and there's little reason to not roll HGs given their incredible versatility. If you have more contracts than you have resources to spend on expensive recipes, rolling HGs can be an efficient way to make use of your T-Doll contracts.

Fairies

A max SL Parachute Fairy is highly recommended as well as a max SL Illumination Fairy and max SL Taunt Fairy.

More detailed recommendations are available in the Isomer Teambuilding Recommendations guide shown below.