500 MA actually does work well against many of the defenses suggested in this thread though as illustrated below:
Attacker Units: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Losses: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Defender Units: 6907 6907 0 6908 0 0 0 0 0 0 0 0 0
Losses: 3687 3687 0 3687 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
0 MA kills 11,061 defense against 1:1:1
Attacker Units: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Losses: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Defender Units: 6907 6907 0 6908 0 0 0 0 0 0 0 0 0
Losses: 3796 3796 0 3797 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
Technically that kills 11,389 troops, 328 more than with 0 MA, but it takes you 179:51:34 to build that offense as opposed to 175:23:25 to build the first offense. Technically it's an improvement vs. that defense (kill 2.97% more troops, take 2.55% longer to build), but not a large improvement, and wouldn't be an improvement at all against a defense that didn't make so many archers. If you're wondering why the axe total changed it's because I'm not trying to push a anti-MA agenda, and gave the MA supporters the benefit of the doubt that they make more axes to keep the build-time balanced when adding MA to their nukes. If I left the axe count the same between both nukes it'd make the MA nuke seem weaker than I'd consider fair because if I just subbed out 625 lc for 500 MA it'd make the stable queue take quite a bit longer than the axe queue to complete which is obviously not ideal.
Against a slightly less archer-heavy defense like the one suggested by Gorth the numbers change to:
Attacker Units: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Losses: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Defender Units: 8288 6217 0 6217 0 0 0 0 0 0 0 0 0
Losses: 4408 3307 0 3307 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
If the defender uses 4:3:3 they lose 11,022 against a MA-less offense.
Attacker Units: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Losses: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Defender Units: 8288 6217 0 6217 0 0 0 0 0 0 0 0 0
Losses: 4573 3430 0 3430 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
You kill 11,433 with 500 MA, an increase of 3.729%, technically this is less due to the extra MA though than it is the extra axes because he made his defense so spear-heavy.
With galaxy's suggested defense of 2:1:2:
Attacker Units: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Losses: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Defender Units: 8289 4144 0 8289 0 0 0 0 0 0 0 0 0
Losses: 4121 2060 0 4121 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
10,302 losses w/o MA:
Attacker Units: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Losses: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Defender Units: 8289 4144 0 8289 0 0 0 0 0 0 0 0 0
Losses: 4407 2204 0 4407 0 0 0 0 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 15
11,018 losses w/ MA, an increase of 6.95%.
In all of these scenarios the MA benefit the nuke, and would seem to imply that making the MA is worthwhile. And, against a decent opponent it probably is, but let's take a look at the troops on this world:
8.64 million spears
6.72 million swords
2.98 million archers
927,757 hc
That gives a much different picture of the typical defense than the defenses simmed above are:
Specifically this turns the typical defense into something like:
1 hc: 3.21 arch : 7.24 sword : 9.31 spears
For a full defense this becomes 804 hc, 2581 archers, 5821 swords, and 7496 spears.
Think that's enough archers for the MA to shine? (Hint: The answer is no.)
ttacker Units: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Losses: 0 0 6157 0 0 3375 0 0 213 0 0 0 0
Defender Units: 7496 5821 0 2581 0 0 0 804 0 0 0 0 0
Losses: 4998 3881 0 1721 0 0 0 536 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 14
Defender loses 13,816 troops if you do not use MA.
Attacker Units: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Losses: 0 0 6313 0 0 2711 500 0 213 0 0 0 0
Defender Units: 7496 5821 0 2581 0 0 0 804 0 0 0 0 0
Losses: 4827 3748 0 1662 0 0 0 518 0 0 0 0 0
Damage by rams: The wall has been damaged and downgraded from level 20 to level 14
Defender loses 13,345 if you do use 500 MA. You just made your nuke take 2.55% longer to build to kill 3.41% less troops. Not exactly a good tradeoff.
So, yes, MA are good against most defenses, but I don't feel they're the defenses that the average player is making, and you should be tailoring your offense to work against the defenses you are most likely to be fighting, not hypothetical defenses that few players actually make.