When discussing Cuotl strategies, Sun Idols frequently feature. It appears they counter everything, from Zeke to Eldar Glass Dragons.
The Sun Idol is But it didn't take a genius to work out the Sun Idol rocked against cannon fodder... but what about stronger enemies? I decided to test against just two enemy units on netural non-attrition ground. Two popular units. Reasoning: The Sun Idol speed. While his attacks are fairly effective, it simply takes too long between each sun beam attack for it to win. However, if the Juggernaut costs twice as much as the Sun Idol, then it would stand to reason. Let's look at the Juggernaut's price... To see if the Rukh is more cost-effective... The Sun Idol is obviously best against small units, and it's trample will completely pwn large groups of infantry with real ease, but it's slow attack, slow speed and apparent weakness to other large units means to use it in moderation.
Cost: 100 Timonium, 300 Energy
HP: 800
Trample: 18 (high)
Siege: 16
Attack: 14
Range: 20
Pop: 7
Speed: 25 (slow)
Armour: Heavy
Size: Large
As mentioned, it is high. However, the Sun Idol moves very slowly and your opponent will usually have no trouble moving the cannon fodder out of the way. However, upon right clicking enemy infantry, the Sun Idol will automatically go to use trample - he will not stop and use his sun beam.
And against standard Vinci Musketeers, the trample obliterates them instantly. It is that strong.
The Juggernaut
It begins with a research cost, unlike the Sun Idol, which is
And from that point, to buy the unit, it costs
When comparing that to the Sun Idol's 100/300, the Juggernaut feels a little cheaper, and it has a cost system which means it will be more effective to build a lot of Juggernauts - getting the most out of the 150/25 research. While it is more cost effective for the Sun Idol when comparing the first Sun Idol to the first Juggernaut, it soon becomes apparent that the Juggernaut is more cost effective on perhaps the 5th unit.
The Rukh
However, the Rukh is a Great City unit. The Juggernaut and Sun Idol only require a large city. It would appear the Sun Idol is simply better than the Rukh - available earlier, roughly equal cost, victory in combat.
I personally was one of those who use the Sun Idol against everything. I would always send them in, trailing my main army to have the beams of light as a bit of support - perhaps this isn't the most effective use? Getting their trample in the thick of things is certainly a good option.