Can I with one build order pay 3 gas and build an Archon right away?

No, you can't.

Tech-required units also require the presence of destroying units on the active planet before the build order is revealed.

I kind of thought that it seemed weird to have such a good unit be so cheap.

That goes for all of the other advanced units too ( i.e. mutalisk to devourer or gaurdian, hydralisk to lurker, dark templar to dark archon). They must change in a separate build order. But that doesn't mean you can't play two build orders in a row to create the unit.

Also, if you are using such a unit on a planet without your base, you can still upgrade it if using a build order on the planet. You can work that into your strategy: using one build order to upgrade your unit and also build a base with the same unit on that planet.

yeah but when you play brood war you will notice archons are not anymore worth to be build. the rise of costs and decrease of power while they may not stand in air-only areas is a bad joke.

our rules: 4 gas, buildable with one build order, 3 build supply needed, +2 support instead of decreased +1

maybe in english version it differs

cyb3k said:

How did you make this decision?

Ivar said:

Ivar said:

Page 38 of the core game rulebook, under the heading of "Tech-Required" Units , states:

"...that means that a player can only destroy a unit that existed on the active planet before the Build order was executed..."