Make KK-Tankki deadlier, the only change is homing grenades which you can just stay away from the tank to circumvent.
Underground Jungle wasps could maybe poison you and bleed poison
Toothy Spiders in the Underground Jungle, they honestly are broken to begin with
All masters have a longer status effect duration
Forgotten alchemist maybe casts his spell several times in a burst,
Green spiders in the underground jungle move faster and bleed acid
Splody mushrooms make more splody mushrooms when they explode for infinite splody mushrooms, OR they can fly and have stronger explosions
Not sure if it's been changed but if it hasn't, turret now shoots lasers EXTREMELY fast to guarantee death if you're in front of them
Not an enemy change but it could work: Remove the safe zones at the start of Snowy Depth and onward
Delirium moves faster and the crystal explodes into chaotic poly when destroyed
Spiral Phantom's second orbs spawned by its main attack go through walls
Angry Phantom is so angry that it deals x2 damage
Cursed crystal bleeds ominous liquid and has infinite attack range so you can die from further away
Not an enemy but destroying an electric trap cube creates a homing thunder charge instead of a stationary one.
Monk has 4 hands for twice the projectiles and twice the spell blocking
Damned Alchemist has larger invincibility field, gains projectile immunity and always has the invincibility field
Rats probably already have a buff but if not then they explode upon death and move really fast.

Ok I have checked, scrap the Monk suggestion and add this:
Laser tank now fires Magic Missiles instead of lasers.

Add custom bosses and give them their own arenas.

And make it so you have to beat them to beat the game and make a new much more unfair final boss.

Originally posted by Beachcraft12:

Add custom bosses and give them their own arenas.

This is a plan I had for a later stage in development, might make it a seperate mod, idk but there is one custom boss if you go to the Magical Temple.

I copy my suggestion here. ;)
Could you add the possibility that worse monsters are added to the original ones, instead of replacing them? With a probability that instead of spawn a normal monster, it spawns the worse version.
That would be so cool!
:pray_stevari_very_hard:

P.S.: I'm still working on a mod where all monsters drop their spells when you kill them. I would love to make it compatible with your mod! :P

r u sure?