For those of you who are getting stuck on the later levels, try using the shield. It is able to block and destroy mines, seekers, and leechers, as well as every type of regular bullet. For instance, I used this combination on level 21: Super machine gun, Leecher, Shield. I could block most of the bullets fired at me, restore some health with the leecher bullets, and keep up a steady stream of fire.
The level of a letter does a lot towards how much damage you can get per word. Yes, it is helpful to use a word like antidisestablishmentarianism, but that alone would do only 28 damage. However, no matter what type (jade, brass, or regular) a ball is, it will have the same letters for each level. Take this concept for instance. The letter B is a level 3 letter. Get a level 3 jade ball and then combine it with a regular B ball if the jade ball isn't already the letter B. Then, if you use it in antidisestablishmentarianism, the word now does 154 damage. All of this just because of one ball. The letters H and M are also level 3 balls, and if you get both of those along with the B ball in the word, it now does 462 damage. You see where I'm going?
Very fun and addicting. I work primarily as a secretary, so I take calls all day, but there is sometimes alot of downtime in between. These puzzles helped me fill 2 hours of that downtime. I also like being able to just stop a puzzle and then pick up on it later. I'm looking forward to completing the other puzzles you've made and hope that you'll continue to make more.
 "Bubble Tanks Arenas"){kind=icon}
 "Clockwords: Prelude"){kind=icon}
 "Easy Kakuro"){kind=icon}