Fun fact: when Star Trek: Deep Space Nine did their first Mirror Universe episode, "Crossover," they tried to get Michael Dorn to appear as the Mirror Worf, serving one of the Klingon guards on Terok Nor, but since he was still filming The Next Generation the schedules didn't work out. Which was fortunate, because later on, when Worf had joined DS9, he got a much more prestigious Mirror counterpart.
Since the Regent was released as part of a TNG series (although he and the "Soldiers of the Empire" variant Worf got the DS9 packaging inserts), the generic bio on the back is all about the Enterprise and peaceful exploration, which isn't much help for the Mirror Universe. In brief, the MU is a parallel reality where everything has been given a nasty twist - a "moral inversion," Spock called it.
But it's not always so simple as good characters being evil and vice versa. Rather, everyone's had something about themselves inverted, so Sisko was (briefly) a rogue who took no responsibility for anything, Kira was thoroughly selfish, Odo believed (also briefly - it's a dangerous universe) in law, even unjust law, instead of justice, Garak's motivations are plain as day, and Quark was (yep, briefly) charitable. As Regent of the Klingon Empire and ruler of the Klingon/Cardassian Alliance, Worf was still a proud and powerful Klingon warrior, but instead of being honourable and introspective, he was brutal, arrogant, and thoroughly tyrannical.
Put this guy next to any other TNG or DS9 figure, and the first thing you notice is that he is big. Michael Dorn's 6'4" tall, plus there's the high Klingon forehead, so Worf here stands a full 8" tall, towering over the likes of Sisko,
and as for Ezri, I don't know how the Regent's regular universe counterpart even found her, let alone had a fling with her. It's not just height either - the body is proportional, with a heavy-set, powerful physique that lets you know he's not just some big guy in a costume, but a genuine warrior who could break you in half without raising a sweat.
The Regent costume was basically the standard Klingon warrior gear, distinguished mainly by the long, heavy High Chancellor's greatcoat - the figure omits the coat, and has a few other minor inconsistencies (for instance, the boots are the newer, sleeker design, rather than the old ones with solid steel panels on the inside forward edges), but there's a distinctive chest element added to the basic Klingon figure body that's accurate to the Regent's outfit, and overall it's a good effort.
The faces on the recent Star Trek figures, and especially the DS9 ones, have been pretty impressive, and Regent Worf doesn't fall short. The only real negative is that the hairline isn't quite spot on - the Regent's hair was wilder and more mane-like than regular Worf's, but the figure takes it a bit too far on his forehead, with the hairline blocking off the Klingon ridges a little too early, not leaving room for them to extend up over his crown a bit before disappearing under the hair. That aside - and it's certainly not something that leaps out at you as wrong - it's all good work here.
Michael Dorn's face and the Worf makeup are faithfully reproduced, both in sculpt and colour, and the expression is quite fitting for the Regent, a mix of Worf's habitual sullen glare with the arrogant hint of short-sighted anger that characterised the Regent specifically. The beard is quite respectable, with fine sculpted detail and carefully applied paint giving a decent result, the lips and eyes are painted cleanly, and a slight highlight on the hair, along with the soft plastic's naturally glossy finish, helps bring out the sculpted texture.
The paint elsewhere is of a high standard too. The primary colours of the outfit - the dull silver jerkin and shoulder armour, the black sleeves and leather bracers, the soft grey pants and heavy knee-length boots - all ring true to their on-screen appearance, with the jerkin in particular deserving praise for a very well-judged ink wash that brings out the detail on it. Painted colours match their counterparts on separate pieces, such as the boot tops above the knee joints, and where there's painted detail such as the belt, the chest adornment, and the plates and spikes on the boots, the work is clean and clear. The only area that might have been improved a little is the hands, which are a touch too light - the silver fingerless gauntlets could have stood to be darkened a bit to better match the metals on the rest of the costume, and the fingers, especially the clenched fists, could have used a wash to darken the recesses.
Looking at articulation, the first thing you'll see is the hair sitting tightly against the shoulders, suggesting an immobile head. That's not the case, however - the hair is soft enough to be moved over the shoulders a fair way to either side, and even tilt up and down a little, and the neck balljoint, hidden at the base of the neck beneath the collar, is stiff enough to keep the hair from pushing the head back to its rest position. Side-to-side tilting is all that's completely blocked, so for a long-haired figure Worf's head mobility is good.
The arms have shoulder balljoints,
bicep swivels, peg elbows, and swivels at both the front and back of the bracers, taking advantage of their design to hide an extra joint, which comes in handy for fine-tuning. There's a swivel waist, below the belt with the lower edge of the jerkin turning with the hips - since it's soft plastic it could have been practical (and better looking) to keep the jerkin in place, and have the hips turn beneath it, but it's no big deal. Instead of balljointed hips, there are peg hips with tilted swivel thighs, again taking advantage of a sculpted element of the Klingon armour to include another joint - it offers some possibilities while posing, but ball joint hips, with the ability to widen the stance, would have been welcome too. Finally Worf has peg knees and peg ankles - and here, swivels at the sculpted seam below the knee would have aided posing without interfering with aesthetics, but sadly there are none.
All told, Worf is really quite mobile for a Star Trek figure - once you get used to the tilted thigh swivels, and how they interact with the other leg joints, you can manage some respectable action poses, which is fitting for a Klingon warrior. But since he is a warrior, those extra joints would have been nice - I'm not asking for super-articulated figures, but this is an excellent figure in many areas, and it would have been nice had the articulation gone the extra mile too, to be not just "good" but "really good."
Diamond Select/Art Asylum don't shortchange their Trek figures when it comes to accessories,
and the Regent is no exception. As if he wasn't tall enough already, he comes with a display base, the same "transporter" base as the rest of the TNG figures had, though has a Klingon logo that's quite fitting the Regent's Imperial nature. There's no pegs, nor peg holes in Worf's boots, but even though he's such a big, heavy figure he's quite stable. No Klingon would be without weaponry, so Worf gets three pieces - the standard one-piece d'k tahg dagger, a Klingon disruptor rifle, and a bat'leth.
All of them are to scale, but in Worf's hands they look small, especially the rifle - not a big prop to begin with, compared to the behemoths Starfleet started producing in the later seasons
of DS9 - which ends up looking roughly the size of a submachine gun at best. The bat'leth is shaped like the Sword of Kahless, with a long central handle rather than three smaller ones, and all manner of extra points and edges and general unpleasantness for whoever gets hit by it. The weapon lacks the Sword of Kahless's distinctive markings - a combination of Klingon names and Syrian weapon decoration elements, styled to resemble a topographic map - but the same shape of bat'leth has been seen elsewhere in Star Trek as an antique, so the Regent's blade being unadorned isn't necessarily an oversight.
He also comes with two extra hands, which pop on and off at the wrist easily enough (though they're spiky, so watch where you push when you're putting them on) - the options are clenched fists, or open hands, with the right half-closed to hold weapons, and the left more open. It's an impressive spread of accessories, but I have to say, I'd without hesitation have lost the base if it had meant we'd get a soft rubber High Chancellor's coat.
Regent Worf is a bit of a rarity in the Star Trek line - naturally enough the line has focused on each show's main characters and variants of them, so recurring villains are in short supply. Since Regent Worf is a main character and a recurring villain, he (along with similar main-cast-villains like Locutus, and the occasional lucky break like Q) can fulfil the role of adding malevolence to your Trek shelf until some Cardassians or Jem'Hadar show up.