-the spells postens can use depends on the cap. StonegaII is devastating in 40 cap. They cast lots of dots which will frustrate mages who just sleep you repeatedly.
-postens will chase any opposing player that they detect; they have no real limit on where they can go. I had one chase me all the way back around the island once. They detect by sound or true sound (never had someone sneak me to test that). when someone attacks the brenner they will periodically reset hate to the person attacking the brenner, regardless of where they are. So, you can't just kite all the postens away permanently.
-postens attached to brenners without flammens will aggro players of the opposite team and hunt them down without mercy. Use this to your advantage to get your postens who don't have a flammen to guard involved in the fight instead of just idling.
-brenners don't regenerate HP. One strategy for winning a close match is to whittle down the opponents flammen-brenners evenly, and then at the end of the match just full-attack and steal their flammens just as time is about to expire.
-when you steal a flammen you have 2 minutes to get it to your own brenner. There is no bonus or penalty for the time it takes to achieve this. Nearing the end of the match, I would tend to hold onto flammens as long as you safely can, since they cannot attack your brenner until you cash in the flammen. One match I stole a flammen with about a minute left to play, and just ran out the back of the opponents base, with the intention of holding it until the match ended. Since only a Paladin was chasing me, I was able to withstand his assault until time expired and we won.
-you permanently gain 1 point every time you steal a flammen, even if your flammen runner gets killed before he returns the flammen. If the other team plays too defensively, a good strategy is to let them hold onto 3 flammens while you protect your own, and just intentionally fail to steal one their flammens to get a point edge. Nearing the end of the match, make sure you bring the flammen balance back to even (shouldn't be too hard since they have 3 brenners to defend and you only have 1) and you will win by virtue of having more steals.