Yes, you can change the enemy types in any level. When you go to the top of the enemy information of a level, you will see that there are 2 or 3 slots for enemies. In Blue Lake Woods I there is only two. The first one is 00 0C, which means dragon with the 1st colour palette, and the second one is FF FF, which is empty. The reason for this is dragons take up two spaces (flying and walking). Tanks also take up 2 spaces and Lions take up 3.Â
So, to change the dragons to tanks you would change 00 0C to 00 0A. Then at the begenning of the information for each individual enemy, you change the enemy type. For example, 0D FF 00 00 04 A8 00 8F would change to 0A FF 00 00 04 A8 00 8F.Â
It is possible to add two enemy types to Blue Lake Woods I as long as you choose two enemies that take up one space. For this example, let's use Hopping Skulls (1D) and Mini Hopping Skulls (1C). You would change the first enemy slot from 00 0C to 00 1D. Then you would change the second slot from FF FF to 00 1C. Then, of course, you would change the individual enemy information accordingly.
Here are the hex codes for each of the enemies:
00 = Fire
01 = Crystal
03 = Alien
04 = Armadillo
05 = Tar Monstar
06 = Ball
07 = Archer
08 = Orca
09 = CrabÂ
0A = Tank
0B = Shooting Tank
0C = Flying Dragon
0D = Dragon
0E - Cloud
0F = UFO
10 = Goat
11 = Ninga
12 = Lion
13 = Scorpian
14 = Twins
16 = Drip
17 = Hand
18 = Tornado
19 = Fire
1A = Drill
1B = Emo Rock
1C = Mini Hopping Skull
1D = Hopping Skull
20 = Heady Metal
21 = Boss' Eye
22 = Shishkaboss
23 = Boomerang Bosses
24 = Bagel Brothers