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