But... I can haz Mil Academy in my HE city and blast out units even quicker still. That multiplication is worth the investment of the build time for WP, IMO. While it's not unit-pumping I usually have a second string military city (my IW city or a capture Cap which usually has settled GMIs) take over.
Just to be clear, the bonuses are additive, not multiplicative.
So, you will get:
(base Hammers) +
(base Hammers) * [(100% for the Herioc Epic) + (50% for a Military Academy)]
You will NOT get:
[(base Hammers) + (base Hammers) * (100% for the Herioc Epic)] *
(50% for a Military Academy)]
As an example, let's say that your Heroic Epic City makes 24 base Hammers.
You will get additive bonuses:
24 base Hammers +
36 Hammers from having the Heroic Epic and from having a Military Academy =
60 Hammers
You will not get multiplicative bonuses:
48 base Hammers and Hammers from having the Heroic Epic +
24 Hammers from having a Military Academy =
72 Hammers
Thus, there is no advantage to "stacking" bonuses in the same City. If it weren't for overflow capping of Hammers, then there wouldn't be a disadvantage, but due to the way that overflow capping of Hammer works, you can actually greatly lose out by stacking these bonuses in the same City.
What I often find is that even without a Military Academy, my Heroic Epic City will start getting too many Hammers and will start to lose some production due to overflow-capping issues.
In fact, the way that overflowed Hammers are capped, the greater your production bonuses, the less base Hammers that can overflow. So, you can often hurt yourself by stacking too many Hammer-based bonuses in the same City.
Let's look at an overflow-capping example. Let's say that your unit requires 42 Hammers to build. In our Heroic Epic + Military Academy City, we make 60 Hammers per turn.
The way that overflow-capping of Hammers works on paper is that you can have AT MOST an equal number of Hammers as the cost of the build item overflowing. In practice, this value can be CONSIDERABLY LESS.
The reason why the value can be less is the way that the amount of overflow allowed is calculated.
Okay, so on turn 1, you have made 60 Hammers. The unit required 42 Hammers to complete. However, the calcuation isn't a straight-up "60 - 42 = 18 overflow Hammers remaining." If it were, then you could overflow almost as many overflow Hammers as your base Hammer value (18 overflowing from 24 base Hammers) while getting a unit for free. Clearly, the math can't be calculated so simply or else you'd have people abusing overflow from a heavily-bonused build item overflowing into a lower-bonused build item, such as a Wonder without production bonuses (like the Apostolic Palace). I think that you can see how quickly such a situation would lead to massive abuse.
Thus, the math gets a bit tricky and I may not even calculate it exactly, but it goes something like the following:
a) 42 Hammers are needed to complete this build item
b) We make + 150% in bonus Hammers (I'll pretend that you neglected to build a Forge here)
c) So, in order to get 42 Hammers, we are required to use up:
42 / (1 + 1.5) base Hammers =
42 / 2.5 base Hammers =
16.8 base Hammers
The game then says that you can't "spend" a partial Hammer, so it "charges" you 17 Hammers.
d) We had 24 base Hammers to begin with
e) We have used up 17 base Hammers
f) We can overflow a maximum of 24 - 17 = 7 base Hammers
So far, so good. However, next is where it gets tricky
g) To avoid excessive overflow, we'll ensure that overflow is capped at the cost of the build item
h) The build item requires 42 Hammers to build
i) But we are making this many additional Hammers:
7 remaining base Hammers * (1 + 1.5) =
7 * 2.5 =
17.5 Hammers
j) 42 Hammers - 17.5 Hammers is still a positive value
k) Therefore, all 7 base Hammers overflow, as expected
Okay, nothing weird so far.
The next turn, you will make:
7 overflow Hammers + 24 Hammers from production sources = 31 base Hammers
The calculations repeat themselves, such that the game still only needs you to "spend" 16.8 base Hammers and charges you 17 base Hammers.
f2) You are left with 31 - 17 = 14 remaining base Hammers for potential overflow
g2) To avoid excessive overflow, we'll ensure that overflow is capped at the cost of the build item
h2) The build item requires 42 Hammers to build
i2) But we are making this many additional Hammers:
14 remaining base Hammers * (1 + 1.5) =
14 * 2.5 =
35 Hammers
j2) 42 Hammers - 35 Hammers is still a positive value
k2) Therefore, all 14 base Hammers overflow, as expected
Now we get to the next round.
This proceed as before, with you making:
14 overflow Hammers + 24 Hammers from production sources = 38 base Hammers
The calculations repeat themselves, such that the game still only needs you to "spend" 16.8 base Hammers and charges you 17 base Hammers.
f3) You are left with 38 - 17 = 21 remaining base Hammers for potential overflow
g3) To avoid excessive overflow, we'll ensure that overflow is capped at the cost of the build item
h3) The build item requires 42 Hammers to build
i3) But we are making this many additional Hammers:
21 remaining base Hammers * (1 + 1.5) =
21 * 2.5 =
52.5 Hammers
j3) 42 Hammers - 52.5 Hammers is no longer a positive value. We have thus exceeded the overflow cap. Not all 21 of our remaining base Hammers will overflow.
k3) So, how many Hammers will overflow?
42 Hammers for the build item / (1 + 1.5) =
42 / 2.5 =
16.8 Hammers can overflow
But the game does not allow you to carry-over partial Hammers.
So, only 16 Hammers actually overflow.
21 remaining base Hammers - 16 Hammers that can overflow = 5 Hammers lost
Now, those 5 Hammers will potentially get turned into Gold using the overflow function. I think that if you are using BUG + BULL Mods, you'll get 1 Gold for every Hammer. If you aren't using those Mods, I have heard people complain about the amount of Gold being even LESS than 1 Gold per Hammer, due to some bugginess in the way that overflow capping Gold-conversion calculations were changed in BtS 3.19, but I haven't done any testing on the subject myself, so I can't say for certain.
Either way, it SUCKS! Your 1 Hammer was supposed to turn into 2.5 Hammers. Instead, you got a measley 1 Gold for it! That Gold wasn't being used effectively to pump out 2.5 Hammers' worth of Military Units!
And we ran up against this "overflow capping wall" as soon as we'd been building our THIRD UNIT! Surely, you plan to build more than 3 units in your Heroic Epic City.
In fact, the next unit, unless you swap the build order to either a Building (which is again an inefficient use of your Hammers in your Heroic Epic City) or to a higher-priced unit (should you actually have the tech to do so, good for you, but if not, then it sucks)... unless you do so, then when you build the 4th unit, you will be losing even more Hammers to overflow capping. Let's just run the math to see how much...
Well, we were able to overflow 16 Hammers from our 3rd unit, so our 4th unit will have:
16 overflow Hammers + 24 Hammers from production sources = 40 base Hammers
The calculations repeat themselves, such that the game still only needs you to "spend" 16.8 base Hammers and charges you 17 base Hammers.
f4) You are left with 40 - 17 = 23 remaining base Hammers for potential overflow
g4) To avoid excessive overflow, we'll ensure that overflow is capped at the cost of the build item
h4) The build item requires 42 Hammers to build
i4) But we are making this many additional Hammers:
23 remaining base Hammers * (1 + 1.5) =
23 * 2.5 =
57.5 Hammers
j4) 42 Hammers - 57.5 Hammers is no longer a positive value. We have thus exceeded the overflow cap. Not all 23 of our remaining base Hammers will overflow.
k4) So, how many Hammers will overflow?
42 Hammers for the build item / (1 + 1.5) =
42 / 2.5 =
16.8 Hammers can overflow
But the game does not allow you to carry-over partial Hammers.
So, only 16 Hammers actually overflow.
23 remaining base Hammers - 16 Hammers that can overflow = 7 Hammers lost
Those 7 Hammers should have been:
7 * (1 + 1.5) =
7 * 2.5 =
17.5 Hammers going into your Military Units
Instead, at best, you will get 7 Gold going into your coffers and you might even get less if BtS isn't calculating that overflow Gold-conversion calculation correctly.
That's a HUGE BLOW to what's supposed to be your Hammer-heavy City "pumping" out units--you might as well not work nearly as many Hammer-based squares in that City, since by working a lot of them, a good portion of your Hammers aren't even being used to create Military Units! What a nightmare!
The best general solution, I have found, is to split up my Military Academies from my Heroic Epic City. Doing so gives two benefits:
A) I can probably build nearly as many units over the course of 10 turns in my Heroic Epic City with or without a Military Academy, meaning that I can get one additional Military Academy City adding Military Units to my empire--essentially I will have nearly the same effective output from my Heroic Epic City (due to losing less Hammers to overflow capping) AND I can get the additional Military Units that the Military Academy City will create during those 10 turns
AND
B) If there IS some overflow capping in my Heroic Epic City, I will actually get to carry-forward MORE overflow Hammers without the Military Academy than with it
To illustrate point b), using our above example on the fourth turn, let's assume that somehow the Military Academy was deleted (say, you removed it using the World Builder or a Hurricane destroyed it--although it's probably not possible to lose this building to a Hurricane, let's just say that it happened):
Well, we were able to overflow 16 Hammers from our 3rd unit, so our 4th unit will have:
16 overflow Hammers + 24 Hammers from production sources = 40 base Hammers
a4ii) 42 Hammers are needed to complete this build item
b4ii) We make + 100% in bonus Hammers (I'll pretend that you neglected to build a Forge here and our Military Academy was destroyed)
c4ii) So, in order to get 42 Hammers, we are required to use up:
42 / (1 + 1) base Hammers =
42 / 2 base Hammers =
21 base Hammers
The game then says that you can't "spend" a partial Hammer, but we don't have partial Hammers here, so it correctly "charges" you precisely 21 Hammers.
f4ii) You are left with 40 - 21 = 19 remaining base Hammers for potential overflow
g4ii) To avoid excessive overflow, we'll ensure that overflow is capped at the cost of the build item
h4ii) The build item requires 42 Hammers to build
i4ii) But we are making this many additional Hammers:
19 remaining base Hammers * (1 + 1) =
19 * 2 =
38 Hammers
j4ii) 42 Hammers - 38 Hammers is still a positive value
k4ii) Therefore, all 19 base Hammers overflow, as expected
In fact, look what happened here. With the Military Academy in the City, we were capped at being allowed to overflow 16 Hammers. Without the Military Academy, we can ACTUALLY ALLOW EVEN MORE HAMMERS to overflow... 19 Hammers successfully overflowed in this case. What's our theoretical maximum overflow?
42 Hammers to build the unit / (1 + 1) =
42 / 2 =
21 Hammers
So, we can overflow as many as 21 Hammers instead of only 16 Hammers before we have to "rebalance" the build items so as not to lose Hammers that should have received Hammer-based bonuses as Gold, which won't receive any bonuses.
Trust me, unless you've got low base production in your Heroic Epic City or have a way to ensure that Military Unit costs are high relative to each turn (such as on Marathon Speed or if you've teched to some really expensive units), you'll be better off in general by separating your Heroic Epic City from your Military Academies. Sure, you could do the math or you could rebalance your build queues, but the general "take away" rule is to separate your Military Academies from your Heroic Epic and to "go home feeling good about your decision."
