Here is the full list of all 72 Variables 2 achievements.
Clear N1
Clear N2
Clear N3
Clear N4
Clear N5
Clear N6
Clear N7
Clear EX1
Clear EX2
Clear EX3
Clear EX4
Clear EX5
Combine a level-3 turret on stage 1
Clear stage with 10000 Gold
Clear stage with 21 system mods
Path Length > 100
Path Length > 200
Path Length > 400
Single Damage > 100k
Single Damage > 500k
Single Damage > 5m
Equip 8 pieces of gear onto 1 turret
Unit corruptive damage > 1 million
Supply 10 times in 1 match
Supply 20 times in 1 match
Defeat Cyborg Slime
Defeat Masochism
Defeat Crazy Racer
Defeat Eternal Sphere
Defeat AI Fanatic
Defeat Genesis
Defeat Octopod Constructor
Defeat Super Hero
Defeat every Boss type
Get 1000 total Variable Coins
Get 10000 total Variable Coins
Get 1000000 total Variable Coins
Get 100000000 total Variable Coins
First draw is for the Jackpot every time prizedraw page is reset
Defeat Eagle Bot 1 time on Difficulty 4+ (Ultimate Challenge)
Defeat Eagle Bot 1 time on Difficulty 7 (Ultimate Challenge)
Reach stage 40 on Difficulty 4+
Reach stage 45 on Difficulty 4+
Reach stage 50 on Difficulty 4+
Complete a round using 1 stage effect
Complete a round using 2 stage effects
Complete a round using 3 stage effects
Internal Difficulty unlocks
Spend Variable Coins to draw 10 Shards
Clear 100 stages total
Clear 500 stages total
Upgrade Variable Coin multiplier 1 time
Upgrade Variable Coin multiplier 2 times
Upgrade Variable Coin multiplier 4 times
Upgrade Variable Coin multiplier 6 times
Upgrade Variable Coin multiplier 8 times
Variable Coin multiplier maxed out
Complete Tutorial
Defeat Mechanical Python
Prepare only 1 recipe and complete 1 game
Battle time of single wave > 100s
Battle time of single wave > 150s
Battle time of single wave > 300s
Own 10 same turrets during single game
Immobilize Enemies for 1000 times totally
Immobilize Enemies for 10000 times totally
Slow down 1 enemy to 10% of its basic speed
Complete 1 game without preparing any Shard
Make attack range of any turret to 30
Complete 1 game with at least 1 acid turret deployed
Complete 1 game with at least 2 acid turrets deployed