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