I'm pretty sure that when you locked the Land upgrade at 3 points you didn't mean for people to maximize Speed and Life then just drop thousands of souls over 1,000 Land
Select targets in this order: giant mechs, UFOs, mechs, heavy bombers, big tanks, tanks, Skeletor, biplane, Nazis; ignore the last two usually. Save for Chain Lightning, the first one. The second one is not so useful. Upgrade Battery, keep your health full. If you are losing HP, you are doing it wrong. Before Wave 9, upgrade Health massively- i.e., to full. Your last upgrade is ideally Chain Lightning 2. Use spare cash on the MiniCoil and when you have MiniCoil 2, ignore the normal soldiers and planes. At the start of Wave 20, ignore everything until Tanks appear, then focus on the Tanks. It is usually wise to stop firing just before a unit is destroyed and hit another one; the Chain will defeat the first enemy.
I have discovered the instructions for the Game With No Instructions!
Arrow keys to move, mouse click in the vicinity of the ball to interact. All walls are made of jelly, so you can drop balls through them, but it is acid jelly, so if you touch them you INSTANTLY lose- for instance, the solution to the last level is to go to the red switch, press it, get the ball then move straight forwards and drop the ball through the enemy gate. To win, place the ball in the area that has been filled with half opacity brush tool.
I looked at my choices carefully the second time, and they were still the same - but when I reached the very last part, I jumped for the end platform, the ledge, and from there jumped off, to hit the coin exactly, from the sky... I am a pro storygamer. The game cuts out the instant before you pass your goal. That is a real way to end your interaction whilst not feeling you failed, being ... you. To the last second ... it goes black when you are in the heart of her ... at last.
Playing as the legendary Allurbase, it occured to me.. why don't the planes just go -around- this one lone attacker? Are they really so suicidal after having lost 11 of their number to this -one- vast aerofiend as to just continue blindly attacking it over and over when it is too slow to outrun them?