he Ironstrider Ballistarii is the second Skitarii walker…
Based on the confirmed rules we have seen so far, it the Ironstrider can be taken in squadrons of 1-6, has the same AV11/11/11 and 2HPs as its Sydonian Dragoon cousin. It also is open-topped, has the Crusader USR (so better chances of good Run rolls if it forgoes shooting) and the outstanding Dunestrider rule (i.e. +3” to any Move, Run, or Charge distances). Like most of the other Skitarii units, it has the “Doctrina Imperatives” rule, the exact details of which are still unreleased, and has a respectable BS 4.
So, what makes the Ironstrider stand out? Well, first of all, it comes with a TLed Autocannon, which can be upgraded to a TLed Lascannon. Importantly, these are “Cognis” weapons, which allows them to fire all Snapshots at BS2, vice BS1. This means that Ironstriders can effectively shoot at Flyers, FMCs, and units with the Invisibility power cast on them at BS3 (BS2 with re-rolls from TLed weapons). Also, they can fire Overwatch at effectively BS3 as well. If you armed a squadron of 6 Ironstriders with TLed Cognis Lascannons, then when shooting at a flyer, they would hit about 50% of the time, meaning you get 3 Lascannon hits… against AV10 flyers, that is 3 automatic glances (unless the Flyer Jinks), against AV11 Flyers, that’s between 2-3 glances almost guaranteed, and against AV12 flyers, you average about 2 glances (again, not counting for any Jinking the by the flyer). As you can see, in addition to their role against ground targets, Ironstriders make a very effective “improvised air defense” to supplement your force.
Speaking of their role against ground targets, Ironstriders can be used effectively in a number of ways. First, with their highly accurate TLed Lascannons (89% chance to hit) and their excellent 9” move each turn, they make a great flanking tank destroyer unit… move up the sides of the board 9” a turn to get good angles for shooting enemy vehicle side armor, then unload with up to 6 Lascannon shots to cripple our outright destroy all but the toughest vehicles in a single shooting phase. Likewise, using the TLed Autocannon option, they can be excellent light vehicle hunters, picking off a transport every turn (even a small Squadron of 2-3 Ironstriders can statistically kill a Rhino/Razorback/Chimera etc each turn.
Against non-vehicle targets, Ironstriders can use their Precision Shots rule to act like highly mobile, vehicle-based snipers. 6 x TLed BS4 Lascannon shots can be an excellent way to cut down a small elite squad like Tau Broadside Battlesuits or Chaos Obliterators or SM Centurions or Necron Praetorians or Ork Meganobz. Use any Precision Shots to surgically remove key models in the target unit, such as Tigurius supporting a Centurion squad (S9 Lascannons vs his T4 means that any wound that gets through results in ID for Tiggy). Similarly, snipe out BA Sanguinary Priests, AM Commissars/Priests, Eldar Exarchs, Ork Nobz, Necron Crypteks, Tau Ethereals, etc. etc.
In terms of “force-multiplying” the Ironstriders, one solid option is to ally them with a Dark Angel Techmarine on a Bike with a Power Field Generator. The TM moves behind the Ironstrider squadron, staying within 3” to give as many of them a 4++ save as possible, and he also moves up to repair HPs of any Ironstriders that receive battle damage but are not destroyed.
Another way to maximize the Ironstriders’ capabilities is to put them on a Skyshield Landing Pad, giving them improved height (so better LOS for their weapons) and conferring an automatic 4++ to all walkers, which basically doubles their survivability against any enemy shooting.
Summing up, if you look at Ironstriders holistically, a good way to think of them is like Scout Sentinels from the AM codex, except better in every category: Mobility, they get Crusader and +3” to all their movement/run/assault rolls; Protection, they have AV11 all around, versus AV10 all around; shooting, they have BS4, TLed weapons, and Precision Shots.