Defense strategy...
	Game Center Achievements...
	In-Game drones...
	Playthrough Strategy Tip...

The first trick you have to make use of in Kingdom Rush Vengeance is of course positioning your defenses. This is a tower defence game, after all. You have set locations you can build your fortifications, and you should immediately pick the locations which are either closest to the spawn of the enemies, or where they can cover most of the path. Set up roadblocks with multiple fortifications which should hopefully tear through enemy health quickly.

Achievement	How to unlock
2Fast 2Furious	Launch 500 Nitro powered Rocket riders.
Broodmother	Spawn 200 Spiderlings.
BUUURP!	Put Borney to sleep.
Can't Touch This	Kill 13 Engineers before they can repair a Machine.
Champion of the Arena	Reach level 10 with Veruk.
Corageous and caring	Find the Gommi Bears.
Curse me kilts!	Find Scrooge McDuck.
Defenders of the night	Summon 13 Gargoyles.
Eternal bones	Help Bonehart to come back.
Far Over the Misty Mountains	Help Bilbo sneak into the mountain.
Feast on this!	Execute 81 enemies with the chainsaw sword.
Feels Good to be Back	Win the first stage with 3 stars.
Final Destination	Destroy 3 mine carts before they reach their destination.
From zero to hero	Win all the Heroic mode challenges.
Go Green or Go Home	Sell 20 towers.
Gotta Go Fast	Call 15 waves early.
Guac-a-Mole	Get rid of those annoying pests and whack 5 Moles.
Hold the door	Fend off the Draugrs.
How to tame your dragon	Defeat Jokull, mother of Wyverns.
I am Iron Man	Defeat Bolgur, Lord of the Dwarves.
I'll be Back	Melt the T-800.
I'm Root	Find the hidden Root.
Ice sculptor	Break the ice from 25 frozen towers.
Ironborn	Win all the Iron mode challenges.
Join the dark side	Turn off all the streetlamps.
Kill Joe Jenkins	Kill Leeroy Jenkins' brother.
Let it go!	Find Olav the magical iceman.
Lord of Winter	Get 3 stars in every stage of the Frozen North.
Mine Cart Carnage	Help DK through the mines.
Mischievous Demon	Reach level 10 with Oloch.
Mistress of Shadows	Reach level 10 with Asra.
Morphball	Find all the armadillos.
Mouserthon	Destroy 50 Chompbots.
My precious!	Take the ring back from Gollum before it's too late.
My watch begins	Slay 300 Draugrs.
No More parties in DK	Get 3 Stars in every Stage of the Dwarven Kingdom.
No Survivors I	Slay 500 enemies.
No Survivors II	Slay 3000 enemies.
No Survivors III	Slay 10,000 enemies.
Not my tempo	Make the horn whisper a song.
Not the bees!	Kill 200 enemies with the bee hives.
Number of the beast	Teleport 666 enemies.
Oh my god!	Hire 5 Trolls.
Presto logs	Use the advanced burning fuel on your furnaces 88 times.
Rightful Owner	Get 3 stars in every stage of the Kingdom of Linirea.
Show me your war face	Summon 50 captain orcs.
Smashing Pumpkins	Destroy the farmer's crops.
Soldiers of fortune	Hire 50 mercenaries.
The skeleton war	Spawn 500 skeleton warriors to battle.
The true king	Defeat Denas, King of Linirea.
They're coming!	Make your crows deal 30000 total damage.
Thunderstruck	Deal a total of 5000 damage to enemies with the basic attack.
Ultra instinct	Make elite harassers dodge 800 attacks.
Unlimited Power!	Kill 5,000 enemies with Vez'nan's powers.
We Are Legion!	Spawn 1,500 Reinforcements.
We Can Build It!	Build 80 Towers.
You didn't see nothing	Find the secret agents.

You don't just have to rely on your defenses, and it's probably best that you don't. You can also use your abilities to place drones and more on the field. The basic drones, Demon Goonies, are great for slowing down enemies, but their damage isn't great - though, you can upgrade them to explode on death, making them much more formidable. Your drones and abilities, such as Soul Impact, are perfect for getting a large crowd of enemies together, and then finishing them all off at once.

You can basically already see the path the enemies will take from the beginning of the game. Use this knowledge to plan accordingly. Some stages will give enemies multiple locations to spawn from, meaning that while it be tempting to stack a bunch of fortifications at the entrance to one, it's not a good idea in practice. These paths usually converge, and it's there where you should place a bottleneck. Orcs are good to slow down crowds, while you use other defenses to finish the enemies.