So today I've played vs Spiral and we are wondering. Reex are said to have a special Fireteam: Triad of 2 Reex and 1 Kriigel, but can we put something else instead of either Reex or Kriigel in the Firetam or it HAS to be 2 Reex with a Kriigel? My opponent wanted to make a Triad of 1 Reex, 1 Kriigel and 1 Taagma (a substitue for Reex). Why I'm questioning this Special Fireteam is because member of other Special Fireteams are allowed to be replaced by Wildcard profiles, and Triad kinda works like everything with it is a Wildcard trooper. Then again for a while (I think now only possible to be seen on some older app version) Reex had Fireteam: Triad skill, but not it seems to be corrected - deleted - and left only with Special Fireteam: Triad annotation.
You would only be able to place Wildcard units with Triad (all units need to have the skill) into that Special fireteam. I don't see any Wildcards in Spiral.
Kriigel have the Triad fireteam skill, so they can use that to form a triad with anything that has Triad. But to do that everyone in the triad needs Triad. The Reex don’t have Triad, just Special. If you use the Special to make a fireteam, you have to use exactly what is specified. In order to do “substitutions” the trooper needs to be specified as a wildcard. Spiral Corp doesn’t have any. Triad isn’t the same thing. And, for the record, the fireteam information shown in Army is quite often wrong. You basically need to bookmark http://infinitythewiki.com/en/List_of_Fireteams