get a combo from the start, you can get to red before he runs to the right to lazer you. Get to gold while you first kill him. Use the gold magic once while he's in the middle, then let him kill you so you can spam him when you respawn.
Protip for when you're really stuck but don't want to brute force: move the pieces out of the way so you can drop the preview without blocking any pieces. Take a screenshot. Now you can get at least a few obvious pieces from the screenshot.
The last two bosses are the ones that are going to take a toll on your heart count. My suggestion: get very good at not losing hearts/collecting all hearts on everything other than those. Those bosses have so many attacks you can barely survive for a second without being hit. However, after you die there are a few minutes of invincibility. I used these few seconds to go inside the bosses; 100% of bullets hit, and it took about 10-15 lives. I only did this on the last boss.
Starts as Eastern warrior. Levels with an army. Visits North Island in east, buys one of the black artifacts.
Goes back to main Eastern island, easily conquers, buys a massive army, conquers northern island, realizes that the character is too powerful for army to keep up.
After the first five cities conquered, stops using troops other than self and bowls through entire rest of game easily.
All the strategy comments are right; even if it seems counterintuitive, you will earn much more by stacking the cakes as straight as possible and only swerving slightly to avoid bombs than by trying to get many edge bonuses. Getting edge bonuses mean stacking cakes far apart and the king loses his combo. If they are very straight, you can get massive combos by simply eating all the cake. In fact, I went from 67k high score with the edge bonus strategy to 85k by eating all of my cakes and getting a huge combo. (+) if this was helpful
When you are running, you are slightly lower down and this is sometimes useful. Like in Hard level 1, you don't even need to use the jump holes to dodge the salt-shooter; just run right through it. (+) if this was helpful.
Lvl 21 Attack gives triple lazorz,
Lvl 21 Magic gives unlimited magic use (magic costs 1 and you kind of have to have already obtained the Magic Elixir to get Lvl 21 magic)
Lvl 21 Health (presumably) grants immortality.
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