The Cultists is a Traveler-59 exclusive unit. Each squad is capable of controlling one enemy unit at a time until that unit dies, and then it is able to recapture another unit. The Cultist isn't a very fast unit, and is vulnerable to anti-infantry attacks. That said, once you make your capture, you should kite the Cultist away from the battle and let your new unit do the talking.
Generally as Traveler, going for Cultists is a good thing, but do so in few numbers. Seek out your opponents higher tiered units and go for them. It must be noted that the Cultist cannot mind control Epic Units, but any other Tier 3 unit is fair game. Once you see your opponent begin to spam higher tiered units be sure to throw a few Cultists into production and keep in mind what Traveler's strengths are as you build your army.
When to build themGenerally when you are behind your opponent on the tech tree process and his higher tiered units are left to face off against your lower tiered army, throwing in a few Cultists into the mix can help even up the playing field. When mixing Cultists into your army, you should be sure you have anti-infantry support nearby to ward off any attacks.
Protecting the CultistsOnce you make your grab, there is no point in keeping the Cultist near ground zero. Kite your Cultist out of battle and out of harms way. The Cultists can garrison buildings and still have control over an enemy unit. This works great when playing a GDI or Nod player. You should also be sure you never leave your Cultists alone to fight. They are great when mixed in with your army so that they are provided some protection. You should ensure that you have anti-infantry, and anti-air present. Gun Walkers work well at this job.
Efficient Use of Cultists If you had to capture say a Rifle Squad to save your Cultist, you can free up your Cultist to mind control something of more value by force firing at another unit. Be sure that you are doing this once you can ensure the safety of your Cultists.
Cultists and WormholesWhen you have a Signal Transmitter up, you are able to pull off a fancy maneuver to change the tide of battle. Place a wormhole near your opponent's forces while you are engaging your opponent. Pop a few Cultists through the Wormhole, capture the most valuable units with the most health, and then slip the Cultist back to safety.
