But first, here are its stats:

Hetairoi with FULL UPGRADES
187 HP, 5.28 speed, 34 hack armor, 56 pierce armor, 15 hack damage. 3.5x bonus to buildings. Approximately 53 hack to buildings.

Cost: 50 food, 81 gold, 3 population

~Tests~
I had the Hetairoi fight 1v1 with: 1 guard tower (with crenellations and boiling oil), 1 Scorpion man, 1 Hoplite, and 1 Prodromos.

Heroic upgrades (no myth techs).
This means that all upgrades available in the Heroic age are purchased, which include Heavy soldiers, and Bronze Weapons. Upgrades are supplied to both the Hetairoi and their opponents.

Hetairoi 137 HP, 4.8 speed, 51 pierce armor, 27 hack armor, 11 hack damage. 3.5x bonus to buildings. Approximately 38.5 hack to buildings.

1v1 Tests
Hetairoi dies- guard tower has 474/850 HP left.
Hetairoi dies- Scorpion man has 456/500 HP left.
Hetairoi dies- Hoplite has 43/143 HP left.
Hetairoi dies- Prodromos has 95/150 HP left.

~Tests- round 2~
Full Upgrades (All myth techs for ideal minor gods [Hermes, Dionysus, Hephaestus]- NOTE: Bacchanalia is included because it is a Dionysus tech and has an effect on Hetairoi). Full upgrades are supplied to the Hetairoi and its opponents, however no myth techs were given to the opponents.

Hetairoi 187 HP, 5.28 speed, 34 hack armor, 56 pierce armor, 15 hack damage. 3.5x bonus to buildings. Approximately 53 hack to buildings.

1v1 Tests
Hetairoi dies- guard tower has 73/850 HP left.
Hetairoi dies- Scorpion man has 371/500 HP left.
Hetairoi dies- Hoplite has 11/166 HP left.
Hetairoi dies- Prodromos has 89/174 HP left.

As you can see, the Hetairoi still is defeated by each oppenent, but does considerably better. And remember that the Hetairoi is not favored versus any of these (except the guard tower). Even in the case of the guard tower, the fact that the Hetairoi brought it down to 73 HP is astonishing. The tower cost 200 gold (the test was done under Egyptian) where as the Het. only costs 81 gold and 50 food. At this "exchange rate" of 1 Hetairoi for almost 1 tower, Posiedon come out with a HUGE advantage

Since Town Centers are always targets, I did some more tests.

Hetairoi vs. Town Center:
Hetairoi dies- Town Center has 2387/2800 HP left.

4 Hetairoi vs. Town Center
Town Center dies- 3 Hetairoi left, 2 at full health and one with 43/187 HP left. It is destroyed in 30 seconds.

These are amazing results, as you have most likely independantly conluded.

~~~~~~Conclusion~~~~~~
With 3 population slot requirements, Hetairoi are somewhat difficult to make room for. But ask yourself: "What else does Posiedon have?"
Hippikons may have higher attack and hitpoints, but their armor is worse, and they dont have that sick bonus vs. buildings.
Overall, Hetairoi are best used against the Egyptians. Hetairoi will quickly demolish their strong structures. Egyptians can really only easily counter Hetairoi with camels and spearmen. With spearmen, their slim .5 bonus is not enough to really be afraid of, and their low HP makes a quick kill for the high-damage Hetairoi. So just watch out for theose camels. Against Egypt Hetairoi are a neccesity and althogh they take a lot of population slots, they will do just as much damage on your enemy's population as only 4 of them can mow down a TC.
Against other civs they should be more carefully used, but still frequently. And if you find that your enemy has no counters for them, mass a ton of them fast, and swiftly knock out every building you can before he builds counters. As Posiedon, you can easily mass attack without leaving many troops behind for defense, because of militia that pop outof buildings.
By getting Hephaestus you can also benefit from forge of Olympus which makes armory upgrades uber cheap. ALWAYS upgrade Hetairoi.
Lastly, Hetairoi are pretty much equivalent to the Norse Jarl, especially with the Beast Slayer tech which gives them a bonus vs. Myth Units.

I hope you got something out of this guide and I see an era of Posiedon possibly coming in the next patch. With Hetairoi, he definately has the potential to dominate in the Mythic Age.

EDIT:
"With 3 population slot requirements, Hetairoi are somewhat difficult to make room for."
I initally thought it was 4 slots, which is hefty. But then thanx to Halimedes i realized it was 3. It is still a high pop. slot number, but 3 rather than 4 makes a huge difference.

[This message has been edited by SilverOsirisAOM (edited 03-20-2004 @ 11:14 PM).]