This is how you beat level 4 on Hard:
Use the annihilator to clear the blockades. Make sure all units stay out of range of spiders. Use Mortor Truck to Lead. The Mortor has enough range to kill spiders with 1 hit without getting hit as long as spiders are on clean ground. Keep Mortor stationed to Lure and Kill spiders until blue refineries are out of money. (The computer should be looping mindlessly, producing spiders and sending them to their death). Finish the game with a similar tactic.
gravity guns take out most of the screen , ranger picks out the leaks and makes very quick work on bosses (about 2 seconds to kill), my hero shotgun noble focuses on tanks, dragons, bombers, and birds.
currently day 110 and still breezing || noble - shotgun w/ 5 slots, instant reload, atkspd 2.5/s, anti air/ anti armor build || ranger - gravity gun w/ leech and knock back. 23 (70%) reload || rogue - laser pistol, very high single target damage, money maker: 10 sense, luck, and killer for exp. || noble - gravity gun w/ leech and knock back, 32 (88%) reload || - all characters have 10 active || - level 12 villa (120%dmg bonus, very important) || - main income: weapon loots (max your inventory), rogue kills (rogues generally get 10x more money from kills), and robbing (500-1200 gold/2action points). || - didnt upgrade wall or sandbag because perfect rounds are still common. || - dont need to spend action points on upgrades unless your weapon has 5 slots (rare). Its much cheaper to purchase higher level weapons from smith. || hope this helps =]
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