Kingdom Rush Vengeance how to beat The lost empire campaign mode with 3 Stars on impossible

Specific level info:
This level is possibly the most difficult of the DLC, if you know how to handle the boss on level 5. The start of this level can be somewhat difficult, but it's mostly smooth sailing until the boss wave.
SAVE YOUR GOLD FOR THE VERY END! In true frontiers fashion, the level has a surprise for you on the boss wave. If it destroys any of the towers near the exit, rebuild.
If it destroys the tower on the left, don't bother too much, just replace harassers with level 1 barracks as necessary.
Assassins are very annoying but they can't instakill heroes. So if you're using a hero less mobile than Asra move him up above as soon as you see some coming. Spam reinforcements up above, too.
If you need to prevent a leak, upgrade harassers. Don't worry about falling behind on the build order, it's really not set in stone.
General DLC and video info:
The new DLC for Kingdom Rush Vengeance - Hammerhold is finally here! I have recorded some tutorials for the new levels, as some of them are pretty hard.
I use only free towers and heroes and try to make my strategy as consistent as possible while requiring minimal skill from the player.
I play on the impossible difficulty and without the Pit Lord upgrade, to minimize RNG. If I used the upgrade I wouldn't know if I succeded because of it, or because of my strategy. So, as you will presumably be playing with it, the levels will only be easier for you.
I also intentionally do not micro Asra or my units efficiently, letting them die even when unnecessary. This is, again, because I'm trying to make my strategy as simple as possible, and as consistent as possible. The levels all get much easier if you get her to instakill a specific enemy or stall enemies with barrack micro. I try to make barrack micro easy, mostly just "place them in a specific spot and don't touch them".

[@Umbra_of_Emberspike]

"This is my third game"
"There is no three without four"

[@QuintanaOmar]

How do you have the DLC already on PC?? I'm very excited for it

[@swipeyplays7798]

"Iron hide"
"This is my third game"

[@Tighnari]

how are you doing it on pc

[@domjogador6389]

how do you play the new campaign without buying anything

[@Derpyisdead]

You have to buy it

[@OndraKyzlink]

@umarabdulaziz927 he is beta tester so he can play it I think

[@Odd_noxious]

@umarabdulaziz927so many say this.
How to fix (probably): update the game, click the level banner, and beat the game first

[@superlegomaster55]

Bone flinger still broken tower I see