What
@Prime said works, yes.
Some other tips (I haven't beat Fector's either, but I used to be able to get pretty close, haven't tried in a while though):
- If you stand diagonally from a large group of enemies, they will bump into each other and move slower (I think)
- I highly recommend buying the first attack power buff before the start of the second world, and the second one before the start of the third world. Usually what I do is buy either the attack power buff (15 coins) or attack speed buff(10 coins) after level 1-2, then the other one after level 1-4, then save my money after level 2-1, then after level 2-3 I hopefully have enough for the second attack power buff (30 coins)
- Try not to use the item hat kills all enemies if you can avoid it, since it prevents them from dropping anything. (If you don't need any more coins, you can consider using it, but you won't get any more items either.)
- For the two mid-bosses, just be patient, hide, and shoot when you can. They can only shoot forwards, so if you can hit them diagonally you're safe. Also sometimes when they match your movements, you can just barely peek out the left side of the fence and hit them and they won't be able to hit you, since they shoot right-handed.
- Save an item that gives increased attack speed for the final boss. I find it quite hard to beat normally without dying, but there's a very easy way to cheese it. At the very start of the fight, go immediately to the top of the map and just slightly to their left, then activate your attack speed item and shoot. The final boss will always start by walking straight to the center of the map, and while they do this they cannot hit you (since they only shoot in 8 directions and you are just slightly to their left). With an attack speed item, you can kill them before they move to be able to hit you.