Enemy's Artemis costs 2 power?

[EdenNov]

I haven't checked it with lvl 3 sensors, but I deduced from various battles that this is the case. Why is that?

[Number43]

Are you sure you aren't mixing up the Artemis and hull missiles?

[Agent_L]

I haven't checked it with lvl 3 sensors, but I deduced from various battles that this is the case. Why is that?

You are right. There are 2 weapons that are *almost* same, MISSILES_2, and MISSILES_2_PLAYER.
The enemy variant takes 2 power instead of 1, but fires in just 10 seconds instead of 11 (that's why you can't beat an opponent in missile standoff)
http://ftlwiki.com/wiki/Weapons#Missiles

I guess it's for balancing reasons. With just 1 power, you would have to bring their weapon room to 0 to stop the missiles and every time they'd repair anything, they'd power up missiles first.
If you think about it, it'd be a nightmare, making shields nearly useless in first sectors.