Nice game, but the game needs to be balanced a bit so that drone spam may be avoided.
Get all general upgrades so you have about 2000 cash to start. Get blaster + damage upgrade, drone + damage upgrade - no other upgrades are needed. Create 4 drones + 2 blasters in the beginning, and keep upgrading as cash generates. Eventually add 2 more blasters. This will keep all the heroes so busy that you mostly don't need to teleport. Even getting hit by the fly-by blaster is fine, the heroes will die so fast your health will get replenished faster. Add some gas traps near the blasters if you want to complete levels faster.
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