I believe I understand what this action does but reading the rules for it breaks my brain.

I understand that reforming simply means a unit turns around its centre point to any new facing. But what happens when engaged?

RR 68.2

"If an active unit performs a reform action while engaged with one or more units, the active unit can rotate around either its centre point of the centre point of any of its individual trays."

I would assume this means simply that all trays rotate to a new facing, but no trays change places. So if I'm flanked for example, I can reform to face the flanker and from thereon Im not flanked anymore. But it may make any figure upgrades susceptible to hits and wounds, depending on unit composition and formation. Especially if reforming to face an attacker from the rear.

Am I understanding how reforming while engaged work?

You got it! In my last game my carrion lancer reformed to present its flank to some spearmen it was engaged with. A wise move, since the Oathsworn cavalry charge the lancer right after. If I hadn't reformed, the significantly more dangerous cavalry would have had my flank instead.

Yes, you rotate around, but remain engaged. The reason it specifies one of your trays is because if your unit is in a 3x1 formation and the side with a single tray is engaged with the enemy, reforming using he center of the unit would disengage the enemy. Instead, you reform using the tray that is touching the engaged enemy. The only way to disengage is to shift directly away from the enemy you are engaged with.

I just threw this together, but this is how I understand the reforming rules. Somebody please correct me if I'm wrong.

So you start off in position A with your 2x2 Reanimate unit flanked by a 2x2 Spearmen unit. You choose to reform. You can choose to reform around the center of your unit, which would result in figure B, or you can choose to reform around the upper-right tray, which would result in C. Both are legal.

I think that is correct, as long as you keep contact with the same opponents edge during the reformation process.

Just now, flightmaster101 said:

I think that is correct, as long as you keep contact with the same opponents edge during the reformation process.

Are the Daqan getting a Martin Luther hero?

Just now, rowdyoctopus said:

Are the Daqan getting a Martin Luther hero?

FFG gonna be mad at me! I wasn't supposed to spoil that!

1 hour ago, rowdyoctopus said:

Are the Daqan getting a Martin Luther hero?

Out with all the ostentation, eh?

4 hours ago, Soulless said:

I would assume this means simply that all trays rotate to a new facing, but no trays change places. So if I'm flanked for example, I can reform to face the flanker and from thereon Im not flanked anymore. But it may make any figure upgrades susceptible to hits and wounds, depending on unit composition and formation. Especially if reforming to face an attacker from the rear.

Am I understanding how reforming while engaged work?

As @Budgernaut showed above when reforming whil engaged your formation still phisically rotates, so your figure upgrades will still be in the front rank if that is where you put them.