That's intended as the bullet damage prevails in this game. The shield has also became weaker, and one of the reasons to that is the fact that it basically forced the player to use Flamethrower / a limited set of towers to effectively deal with Icy. As there are much more towers who deal a bullet damage, the amount of possible scenarios of dealing with Icy's shield grows, still Flamethrower and some other towers are largely effective vs unshielded Icy enemies

But the problem is that the best option to solve the ice is the missile, and the missile will directly damage the main body, and the towers that other bullets damage are very low against the ice, and it is difficult to have a situation where only the shield is dropped to hit the flamethrower.

The point is, there should not be a "best option" to this - there should be multiple. If Icy proves to be too strong, the enemy itself or its shield will be nerfed. For example, currently the shild is equal to 30% of Icy's max HP and indeed it may be a bit too strong (also Icy has lower HP than many other enemies to compensate the extra shield), which means that towers with efficiency of 30% vs Icy should deal with its shield in the same time a tower 100% effective vs Icy can deal with its unshielded body. At the same time, shield does not negate all damage - it just drops it down to 20% for any non-bullet damage type, which means you can break its shield even with a Flamethrower but using Splash or some other tower with a bullet damage type should help with that.

Ice is indeed too powerful - mainly because it ignores control. Of all the enemies in the current version, the most difficult one is the Ice - also because Gauss can't kill it directly. Flamethrowers and Venom do no damage to ice at all, if the shield is not broken first. This may be a bug, including in version 1.8, which states that the shield is reduced from bullet damage, but in fact the shield must be completely eliminated before it can deal damage. The missile's ability to deal with cold ice is far ahead of scattering, range reasons.

Indeed, it receives 20% of a regular damage and has 100% immunity to Burn and Venom. This is not intended - I will lower down its debuff immunity to match the regular damage immunity (to 80%). Nice find!

I've reviewed the code - actually, there's no bug there. Shield only gives a full immunity to STUN / SNOWBALL / BLIZZARD / FREEZING (control) debuffs - as soon as it drops, the enemy is vulnerable to everything.
Actually, Icy enemies are 150% vulnerable to BURN and they burn even with the shield on, which means that while non-bullets perform badly vs its shield, Flamethrower is one of the most effective non-bullet towers vs Icy's shield.

I could change the efficiency of bullet towers vs Icy to make them act as a shield-breakers, but current picture looks like this (Tower type vs Icy efficiency):

• Basic 50%
• Sniper 25%
• Venom 50% (projectile first deals a bullet damage)
• Splash 150%
• Multishot 100%
• Minigun 25%

So currently Splash and Multishot are good for dealing with Icy's shield. If you believe some other tower has to have a higher efficiency, Minigun, Basic and Sniper are possible candidates. My thoughts on this:

• Minigun may be OK if it receives a buff vs Icy, somewhere between 50% and 100%, if it does not make Minigun too universal. Actually, it may act as a difference for it vs Sniper
• Basic has a low damage cap per tile - while players will rarely use it on a higher waves, it may help with Icy's shield in the early/mid stage of the run, and then Multishot or Splash will have to be used
• Sniper is already quite useful and may be overpowered, I don't really want to make it more effective vs Icys

The Flamethrower does deal decent damage to Ice, but the Flamethrower is usually placed at the outlet, making it difficult for him to damage Ice without a shield. If Splash can easily break the shield, then it can solve the ice alone. If you want to build a flamethrower behind a road, it's not at all as good as building a missile - even a flamethrower and a splash together are not as effective at dealing with ice as a missile tower, because the missile tower has a larger range than they all combined.

The problem at the moment is that it's rare to break only the shield, whether you're using a splash or a missile - the main tower that currently solves the ice. They will all directly damage the ice itself, and when they don't do enough damage, the ice will become difficult to deal with. There is no tower that can break the shield quickly, it cannot be slowed down, it must be dealt with a skill immediately (other enemies can be dealt with multiple waves together with a skill). Ice is also uncontrolled and can be dealt to it for less than half the time of other enemies, and it often appears with healer (with higher health and health regeneration), which makes it seem so powerful to all types of enemies.

Corrected a bug where Venom's bullets deal poison damage. This can be observed in light. Or, because the 203 bullet damage can penetrate the Ice Shield, but the Venom bullet cannot.

What I'm hoping for is to weaken the ice itself, and not to increase the efficiency of the bullet damage tower against it. Lower its health, or change its shield mechanics to make it easier to break - if it can be controlled, it's much easier to deal with.

Keeping the thread open for feedback. If anyone else believes there's a severe issue with Icy's shield, they can leave a note.

I've simplified Icy's shield behavior:

• If it still has the shield, all damage goes into the shield first
• Bullet and Fire damage is not reduced
• Control debuffs can only be applied if enemy has no shield
• If damage dealt in a moment is larger than the remaining shield, it will only break the shield and won't reduce the actual HP. It means that shielded Icy enemy can survive a Nuke or a Gauss shot if it has a shield, but it will break the shield so this scenario works just once per enemy