Many viable winning strategies. Flame gas works well with ice, terrible against jet packs. Blast turrets in a tight pack can do massive burst damage, but are weak against hackers. Lots of boosters can give you max shields and 10k money quickly, but don't do any damage.
Got lv.12 , not sure why it worked, I just levitated over and jumped and fell and jumped again. Somehow I was able to jump again when I didn't expect to.
Could only get 2500 gold twice now, first time bugged, second time I lost versus last boss. I think the only way to hurt the king is to pick up treasure, my attacks didn't seem to hurt him.
Upgrades don't seem equal, the lance from stables seems the worst upgrade in the game. May have to restart or something only buying the most powerful upgrades in order to beat the game.
Those 50 hippos are almost impossible to beat, once the double arrows appear and say escape, it is over. Not much chance to escape, and even then you usually get caught right away.