The most complex game?

[Taqwus]

Keeping friends in SMAC was mostly a matter of bribing, just like in Civ II; the AIs in fact always knew what tech and money you had so that they could ask for particular techs or particular fractions of your money. Bizarre, silly, and stupid when the AI was in no position to make demands, or when it'd fare better continuing economic development than war. In both Civ II and SMAC, extermination frequently seemed the best way of dealing with the inane flood of demands and provocations...
SE IV was quite complex WRT ship design; it arguably rivals MOO2 in that regard. While it lacks, say, the assorted weirdness of the 'SPECIAL' components, there are enough components and they're balanced well enough that there's no "ultimate" ship design. You don't, say, have a situation where everybody builds high-powered beamers and the side which shoots first completely annihilates the enemy fleet in one salvo. Damage is more important because repair takes time and components get trashed, supply matters, beams don't always hit (for *most* ships, heh... Religious Talisman of Targeting, anyone?) and what ships could do varied more (like open warp points, drop mines, drop off troops /during/ combat, etc). Interesting. The same complexity and modability makes it hard for the AIs to deal with, however.