Heroes: Sapphira & Valorios
Spells: none
Towers: Archer, Sniper, Well, Lightning, Holy
Start with 2 archer towers right at mob's enterance & start to attack enemies with Avatar right from the start
As soon as you have 180mana place Well by the top gate
The rest just spread all towers you have on hand (my lay out on picture), Spipers in furtherst from the road places. Upgrade Archers with poison, Lightning towers 1:2 at least. Dont bother with Holy until 8th wave when you'll have tons of mana to spend. Both summoned heroes goes to top gate