Here is the full list of all 74 Kingdom Rush achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Fire the Sunray 20 times.
Complete the campaign in Veteran mode.
Defeat Moloch the Demon Overlord.
Defeat 9 legions before they replicate.
Defeat Myconid, the Rotten Fungus.
Kill 25 Shrooms without them poisoning your soldiers.
Discover the hidden monster under water.
Defeat Lord Blackburn to avoid war between kingdoms.
Capture the attention of the mysterious crow.
Kill 15 Wererats before they sicken any soldier.
Find the ninja master rat.
Defeat Ulguk-Hai the Troll Warlord.
Find the 5 legendary lost ice-shrooms.
Defeat 10 Troll Pathfinders while they're treading on ice.
Find the elusive acorn.
Defeat Sarelgaz and its minions.
Help Fredo escape.
Do not let The Kingpin escape.
Defeat Gul'Thak and its minions.
Have your Elves deal 10000 points of damage.
Complete all iron stages.
Defeat Greenmuck and its minions.
Complete all heroic stages.
Complete the campaign.
Defeat Vez'nan.
Have your soldiers survive the explosion of 300 demons.
Build 4 Tesla towers in any stage.
Kill 300 enemies with electricity.
Build all 8 towers specializations.
Earn 45 stars.
Shoot 100 missiles.
Defeat J.T.
Snipe 50 enemies.
Drop 1.000 or more bomblets with the cluster bomb.
Polymorph 50 enemies into sheep.
Summon 5 rock elementals in any one stage.
Change soldiers' rally point 200 times.
Kill 10.000 enemies.
Throw 500 or more axes.
Sell 30 towers.
Have your soldiers regenerate a total of 50.000 life.
Have a single barbarian kill 10 enemies.
Free the sasquatch on the Icewind Pass.
Send 1.000 soldiers to their deaths.
Kill 50 enemies by poison damage.
Earn 30 stars.
Train 1.00 soldiers.
Teleport 250 or more enemies.
Disintegrate 50 or more enemies.
Have your Paladins heal a total of 7.000 life.
Have your Paladins perform 100 Holy Strikes.
Hold 500 or more enemies with Wrath of the Forest.
Have at least 3 Imperial Guards survive in the Citadel.
Defeat The Juggernaut
Train a hero up to max level.
Recruit max elves at The Silveroak Outpost.
Kill 10 or more sheep with your hands.
Catch a fish.
Upgrade all basic tower types to level3.
Train a hero up to level 5.
Earn 15 stars.
Sell 5 towers in a single mission.
Kill 100 enemies with meteor showers.
Use Rain of Fire 5 times in a single stage.
Build 150 towers.
Open 5 information cards.
Kill 2.500 enemies
Build 100 towers.
Build 30 towers.
Kill 500 enemies.
Call 10 waves early.
Call a wave within 3 seconds of the icon showing up.
Call all waves early in a single mission.
Kill one enemy.