Big, massive, hexagonal shields from the havoc shield bubble are indeed impressive, however, the energy consumption of the havoc shield is staggering, the most energy hungry shield as of now. The havoc shield although massive, is difficult to sustain unless you are made of batteries or contain battery cores. (See "Common mistakes that lead to premature tech destruction", mistake #0 on why you should avoid being made of batteries).




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To give a bit of perspective, before BF came out with shields, the normal HE tech with shields used the HE havoc shield most of the time, HE batteries were not around too. Throughout the early days of this situation, all HE techs had negligible shield strength and you would rarely even consider them having a shield in the first place. It simply did not matter as they were never large enough to sustain its power demands without experiencing an RCE of a ton of GSO batteries before the shield went down. We however as players can build big and much.. much larger than the maximum size found in enemy mission techs. Rouge (randomly spawning) techs however are an exception to this perspective, even back then as they can easily be much larger than the largest enemy tech in a mission.

We however as players never had issues sustaining a havoc shield as we can just build bigger and add more batteries, this goes to show how energy hungry the shield is, too hungry for small and medium techs that are not made of batteries. In comparison, a Ven tech with Ven shields would refuse to go down and in some cases, able to sustain an exposed Ven cab from AOE damage until it eventually looses power.

A single massive shield that protects you from all damage does prevent all damage, but goes down much faster than a batch of smaller shields which can experience AOE damage for repair bubbles to repair. (Exact statistics are not provided as said in the guide info, this is what I was referring to.)

So in consideration, using a single, massive shield offers a very fine limit of protection. It's reliable but difficult to sustain. In almost all cases, it is better to use multiple smaller shields along with repair bubbles for the sake of efficiency. It would make you last longer by not depending on a single form of defense as a shield.

The worst design failure tattle tail is when you still have energy but the tech is destroyed anyways. Ideally in all situations, the batteries must expel all EPs before the tech is destroyed, if not, then you likely designed the tech poorly. At least spam some more repair bubbles in such a situation or use larger repair bubbles. The havoc shield does help with this, but then it just drains more power compared to some added repair bubbles. So how about reaching a middle ground? Well, that's the perfect answer to making a tanky tech!

If you have small shields that can reduce explosive damage on blocks without taking too much power in doing so, the repair bubbles (preferably Ven and or GSO in prone-damage-zones) will be more than capable of keeping blocks in good condition while keeping net energy use lower than a perfectly placed havoc shield (absorbs all damage). I recommend the combination of BF shields and Ven/GSO repair bubbles as the shield is not too large and what little damage that does get through is repaired at a low energy cost. This interaction increases tech energy efficiency significantly as the shield is less power hungry and sustained damage is repaired at negligible energy costs.

If you are curious about this in live action, see the TT Naval Warfare Challenge video Round 1 Part 1 on YouTube or Twitch, time stamp: 1:15:00.

Stacking shields has no benefit, it only drains more power. Shields act as a form of barrier for all enemy projectiles, completely impenetrable until power runs out. (Only 2 projectiles bypass shields in TerraTech). There is absolutely no reason in stacking shields of the same size.

Creating a solid wall of shields out of sphere projectors is EXTREMELY inefficient (oh and don't bother with Directional Shields, they offer next to no efficiency bonus compared to the lack of coverage). The added shields aren't even "pulling there own weight" so-to-speak as other shield bubbles are minimizing their surface area. Shields operate based on their independent interaction, when a bullet hits a shield, the projector that made that bubble uses EPs to absorb the shot. The interaction is completely isolated, even an AOE explosion only affects a single shield bubble in energy use and that is from the bullet/projectile of the AOE weapon, not the explosion itself! Having shields cover each-other achieves nothing. The only time a shield uses energy to reduce damage is when something hits it, and that something is stopped right then and there. Having multiple layers of shields does nothing in preventing damage. All this does is add more shields to maintain. The only time a bullet will not hit the outer most shield is when ALL shields are out of power.

I can not stress this enough. Shields are an intangible barrier! NOTHING gets pass them except the air of the atmosphere. You need only one shield to stop all incoming fire as the shield is A PERFECT BARRIER.

NOTE: The only exception to this is adding a small shield under a large shield incase an enemy tech goes inside the large shield and fires within that shield completely bypassing the outer barrier as normal bubble shields are non-physical and only absorb shots that land on their surface. (Fun fact: they used to be physical!)
Stacking repair bubbles however is much more viable, repair bubbles are cooperative, having 2 repair bubbles cover a single block doubles the repair rate, energy maintenance, and energy consumption to repair, but you are getting the additional repair rate from this stacking! Shield bubbles don't give you a reward for stacking besides creating a non-perfect cylinder which has no proper practical function. Adding another repair bubble does the effects of having another repair bubble. Its one more repair bubble to heal blocks and maintain energy where as for shields, two of the same shields in one area is just 1 shield with double energy maintenance. Might as well remove 1 shield and give the other double energy drain while powered.

(Also note that some TT weapons can bypass shields but these are very special weapons).

Ever wondered about the efficiency of a repair bubble vs a shield bubble?
Ever wondered how a tech would do if it was made of a hoard of repair bubbles instead of a typical shield?
You will be shocked to the answer just like I was when I found out.




First off..

• No shield means AOE weapons will have a field day.
  
• Blocks are directly exposed to fire and can pop off if the tech is not designed to handle this problem.
  
• Shields are the main way of converting the EPs in batteries into survivability. They are inefficient but can convert energy into health in massive quantities very easily while repair bubbles have a VERY DIFFICULT TIME converting all EPs to survivability (although for a special reason...).
  
• Lasers are very scary. Especially the actual laser weapons (the beam ones) thanks to lasers having a 2x damage bonus to hull and armor. (This assumes you have lasers that can aim unlike in Vanilla where target prediction is not a thing. Otherwise only continuous lasers apply).
  
• You are vulnerable to alpha strikes insta-killing you.
  
• If you don't have the Explosion Nerf mod, the broken AOE damage physics of TT WILL END YOU and make everything here meaningless... Seriously, vanilla explosions are a game balance disaster due to their lack of AOE damage falloff. (Less damage the further from the explosion).

Now with that out of the way.... I have only done this once officially as lasers hard counter repair bubble spam, so I always use at least Ven shields but have obtained large experience in the one instance.
Also note that this one instance was using the Darvin's Adaptive Armors block mod that features heavy armor (though not of the "armor" material due to limitations) but this should still apply to HE six blocks at least.

So what's the efficiency of repair bubbles vs shields? We will do Shield-Repair (X:Y).
GSO shield vs GSO repair I found to have an efficiency of 1:10....
One... To.. Ten.. GSO vs GSO...
A GSO repair bubble has 10x the efficiency of a GSO shield bubble... And that was with spamming repair bubbles.
Now you can take this with a teacup of doubt as this came from a small scale source/scale of testing.
I had a tech that had shields which would last about a minute or so under relentless fire. Would have enough power for one tough combat mission.
-Swapped to pure repair bubble spam. (GSO shields became GSO repair bubbles).
It would be able to do 5 tough combat missions before running low on power and barely loose a bar of energy on the energy indicator after one tough combat mission at times. (Until AOE bombardment comes in, then it's something around 1:2 efficiency).

Repair bubbles have ridiculous efficiency compared to their shield counter parts. This makes sense as you need many repair bubbles to have the same survivability aid as a single shield bubble but as someone who always had some form of shielding, I was in disbelief at the ideal potential efficiency of repair bubbles.
So the reason repair bubbles have difficulty keeping you alive till your batteries run out is because they use too little energy to drain them before your overwhelmed. Not because they can't keep you alive but because they make EPs last much longer than HPs.

With this in mind, using larger repair bubbles when not using shield bubbles is HEAVILY recommended as the larger repair bubbles would still be more efficient than the small shield while also healing more. (I have to update my guides that repair bubbles lie about their heal rate and quantity, meaning VEN has least repair rate, highest efficiency, and GC the highest rate, lowest efficiency).

The problem is getting enough of them to last against heavy fire.. And not encountering lasers (that can aim).

A rather short edition to the series, but it is rather simple.
To summarize:
Having small shields with repair bubbles backing them up is more energy efficient in every way (as I have experienced) than having an impenetrable, single shield. Besides, what if the enemy gets inside the massive havoc shield? Quite a precarious situation if I must say..... Unless you have an internal small shield in case this happens. Like a venture shield bubble next to a Havoc shield generator.
Repair bubbles are just way too efficient to not use directly (having shields take all damage and have no damage land on the tech before energy runs out means the repair bubbles were never used). They can increase energy efficiency to a far greater extent than I see is worth using an impenetrable shield. Something like double the efficiency that causes triple the survivability.. So ideally, you have shields just large enough to minimize the blocks hit by AOE and prevent lasers from hitting blocks while also minimizing shield size and maximizing repair bubble support. It is possible to have repair bubbles tank AOE damage more efficiently than a shield that prevents AOE damage onto all blocks and doing so essentially keeps block survivability constant while increasing energy efficiency, which in-turn increases survivability as the shields last longer. I recommend GSO repair bubbles and a mix of GSO and BF shield bubbles depending on your tech size. BF for large medium techs and larger, GSO for small and medium techs.