Rounds 1 - 10
– At the beginning, you’ll want to focus on placing the Gun Tower in the lower centre of the loop and upgrade it to level three.
– Now place a second Gun Tower two squares left of the first one and upgrade this fully too.
– Bringing in a few items (ideally Smart Mines and Spanish Flu) will certainly make it quite a bit easier to prevent any units from sneaking past. So be sure to drop a Spanish Flu by the exit (it’ll take out Hazmat’s, so don’t worry).
– Look at the screenshot above and block off the path to the exit first with basic towers, then guide the runners to the fire path in the top-right corner of the map.
– Make sure all Gun Towers in the centre of the map are fully upgraded to level three before round 10 starts, as the Fokker planes will zip past super fast if you’re not careful.
Rounds 11 - 20
– With the majority of the redirection in place, focus on getting a Spark Tower right in the middle of the loop (on the bridge). Upgrade this then place a Polymorph Tower in the very central four-square big grid to slow all planes and units down (if you haven’t unlocked/saved up enough for it, it’s highly recommended you do as it’s the only tower that can slow down Stubborn Runners).
– Upgrade the Polymorph Tower to level three and then replace the very first Gun Tower you put down to a Spark Tower.
Rounds 21 - 30
– Place a Hive Tower in the same location as the Polymorph/Spark Tower as its Radius will work really well against the units and the planes.
– Swap out the Gun Tower in the same square with a Spark Tower and fully upgrade it.
– By Round 28 you should have maxed out your Airstrike, so use it when all enemies are on the screen for a quick and easy cash boost (don’t worry, you’ll re-max it out before Round 50 again).
– Optional thing you can do on Round 30 is to pause the game when the Stubborn Runners are close to the two Momma Tanks and place a Smart Mine on their heads. Kaboom! Easy combo.
Rounds 31 - 40
– Left of it - across the trench - place a Spark Tower and upgrade this to level three too.
– Place another Polymorph tower near the entrance to the trench and nearby set a second Tesla Tower down to cover the central area fully from plane attacks.
Rounds 41 - 50
– Be careful when you reach Round 49 as a few sneaky runners ma y make it to the exit, so make sure you’ve got a Spanish Flu waiting to greet them.
– Finally, if you’re not going for Endless Mode, then during Round 50, wait for the second - and final - wave of Stubborn Runners to appear. Hit the Airstrike button for a quick and easy finish to the runners and the Hindenburg. Nice.