You want Aegislash to go last so that you retain Shield Form when your opponent attacks. This greatly reduces the damage it takes while letting it retaliate with its super strong attacking stats then immediately change back to defense.
Gyro Ball. You always want to him to go last cuz of Stance Change, and Gyro Ball just brings more pain.
Brave is pretty obvious, less speed, more power.
Iron Head almost always does more damage then Gyro Ball
Aegislash needs to have like 1/4 the speed of the opponent to really make use of Gyro Ball over Iron Head. Even with a Brave Nature, 0 Spd and an Iron Ball that is kind of difficult to reach except against fast sweepers (none of which are weak to Steel afaik...Mr Mime maybe?). Aegislash is slow, but it isn't slow enough for Gyro Ball. If you're going to use a Steel move, Iron Head is better most of the time.
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