Here is the full list of all 44 Heavy Storm Shadow achievements.
Build the affinity with Rita, pilot of the Obliterate IV, to 5.
Build the affinity level with Sif, pilot of the Thunder Strike, to 5.
Achieve one victory at the challenge level of 9 on the Snowfield.
Build the affinity level with Alicia, pilot of the Storm Caller, to 5.
Achieve one victory at the challenge level of 9 on the Lunar.
Defeat Meteor Scorpion.
Achieve one victory at the challenge level of 9 on the Desert.
Upgrade the auxiliary system to the max.
Achieve one victory at the challenge level of 8.
Upgrade the defense system to the max.
Achieve one victory at the challenge level of 7.
Unlock 5 primary weapons.
Achieve one victory at the challenge level of 6.
Achieve one victory without any damage in single battle.
Achieve one victory at the challenge level of 5.
Achieve one victory at the challenge level of 4.
Upgrade the fire control system to the max.
Achieve one victory at the challenge level of 3.
Achieve one victory at the challenge level of 2.
Increases critical chance of the primary weapon by 100% in single battle.
Achieve one victory at the challenge level of 1.
Achieve one victory without overheating the energy tank.
Defeat Ice Plague.
Unlock all mechas.
Achieve victory without BOOST in a single battle.
Clear the Tundra map once.
Defeat Giant Umbrella Spider.
Defeat Slime Fish.
Slay Faceless.
Defeat Eggsack Spider.
Clear the Moon map once.
Slay Giant Spider.
Defeat Toxic Stinger.
Achieve one victory without any airdrop support in single battle.
Defeat Desert Scorpion.
Beat Wailing Sprout.
Defeat Bone Spikes.
Clear the Desert map once.
Defeat Tortoiselia.
Slay Umbrella Spider.
Restores more than 120 HP in single battle.
Defeat Scythe Rhino.
Defeat the Creeping Barbs.
Build the affinity level with Cecil, pilot of the Hermes, to 5.