Optimus isn't a stranger to combination over the years but generally his combinations fall into two types: combining with his trailer and combining with another robot.
Combining with his trailer pre-dates Transformers itself when Optimus Prime's ancestor Battle Convoy received a new trailer he could combine with Powered Convoy which in turn became the Transformer Ultra Magnus. Optimus' first new incarnation Powermaster Optimus Prime combined with his trailer as did the Optimus Primes from Robots in Disguise, Armada and Cybertron. A similar idea is used by the Victory Autobot leader Star Saber who is in no way shape or form Powermaster Optimus Prime but done as a jet!
The first Optimus Prime that could combine with another robot was the Japanese version of Powermaster Optimus Prime, Super Ginrai, who could combine with God Bomber to form God Ginrai. Star Saber could combine with Victory Leo to form Victory Saber. RID Optimus Prime combined with RID Ultra Magnus (Ultra Magnus' Japanese name God Magnus is a homage to both the original Ultra Magnus and the combining with Powermaster Optimus Prime God Bomber). All three Unicron Trilogy Optimus have a combining element: Armada Optimus combines with both Jetfire and/or Overload, Energon Optimus combines with either Omega Supreme or Wing Saber and Cybertron Optimus combine with either Leo Breaker or Cybertron Wing Saber. Even the Movie series has had a go at the idea with Revenge of the Fallen Optimus Prime combining with Jetfire.
But you say combining to Transformers fans and one thing instantly springs to mind: the Scramble City/Special team style of combining with 4 smaller robots forming the limbs to a body formed from a larger robot. Transformers has tried many other styles of combining and this is the one fans keep coming back to: the first combination system, as opposed to combining robot, used in the Transformers line. Transformers has returned to the idea more than once, notably with Energon's three combiners made of 4 basics and a deluxe but it didn't involve Optimus Prime. The closest Optimus has got to it was the Energon version which came with four drones that could be attached to Optimus to form a larger robot. Transformers fans, being traditionalists, didn't like it because, like Power Core Combiners the limb drones didn't transform into robots. Power Core didn't have an Optimus though you can argue that Smolder is meant to be one while Crankcase is all but a Nemesis Prime. Another close call is Cybertron Optimus Prime who is designed to have interchangeable add on arms. It's a great idea spoilt by only just one toy, the aforementioned Leobreaker, being released that took advantage of being able to combine with Optimus in this way. I'd have loved to have seen more Voyagers that combined with Prime in this way.
There is one other toy we should probably look at when talking about combiners & Optimus Prime and that's the Protectorbot leader Hotspot. If Hotspot were the natural cxolour for a fire engine, red, then he'd look at lot like Optimus Prime. Their head's are *very* similar. Have a look at Hotspot's repaint Fire Chief and you can see the resemblance, it's just a shame the chest is now orange and some of the blue has inexplicably remained. Was Hotspot meant to be a Fire Engine Optimus in it's original Diaclone form? We will never know.
So there's no previous Optimus Prime that acts as the core of a multi bot combining toy. However that's now changed with the Combiner Wars Voyager toy,
There's very little clues in his stock photos that Optimus is a combiner, though there are some pieces which if we'd looked carefully at at the time might have caused us to ask some questions, especially as we knew that Superion and other combiners were on the table for 2015. In retrospect it's quite a clever trick by Hasbro revealing the toy but not telling us everything about it at the time. What we know about it's combining ability comes from one not very clear picture and by inference from his remould Motormaster and Motormaster's combined form Menasor. Optimus Transforms by the front windows of his cab and first third of the cab sides splitting in two and folding back to form the shoulders. These are folded back against the middle third of the cab, with the exhaust pipes and the remaining cab third on his back. Now look at Menasor. There's the cab windows and exhaust pipes on his chest: so the front of the combined mode is the back of the robot mode. What of the last third of the cab? Well on Menasor that appears to be opened out across the chest and the car chest plate inserted into it. Sure enough a peak at Motormaster's vehicle mode and Optimus vehicle mode reveal hinges on the side of the vehicle and a split down the back of the cab to allow it to open out. Within, I suspect, is housed the combined mode head and perhaps the feet/hands. There's also some hatches on the robot mode legs that seemingly serve no function: they might also hide combiner parts. But if you look again at Motormaster's vehicle mode there's something attached to the back of the cab that looks like the combined mode waist plate. Sure enough Optimus has a piece there too which I can't see used on the robot mode. Finally Motormaster's weapons merge to become his combined mode sword: a look at Optimus' weapons makes it obvious that they too fit together to form a larger gun.
Lots of pictures of Menasor and Superion emerged, including a nice set of in hand pictures of the Aerialbots but we had to wait until the fiorst weekend of Decembver 2015 to see more of Optimus when he was shown at a Singapore Toy Event and then the combined mode was finally unveiled followed by an in hand gallery from Taiwanese blogger Blacklai.
The Optimus toy vehicle mode is, for the most part, quite traditional. He's a flat fronted truck, like the original Optimus Prime. The cab is red, the flatbed is blue with two wheels at the back and one at the front on each side so we've got the basics right. A lot of the front of the vehicle is made from two types of grey plastic, withthe window units being painted over. I think moulding the lighter grey in red would have worked better or at least applying red paint along the top of the front window and round the wide windows whichare themselves unpainted. There's painted windows on the back of the cab too, a feature similar to those on Cybertron Optimus Prime. These have a blue panel folded up in front of them. On top of the the flatbed is a trailer hitch/engine with pipes sticking out the back - this is formed from his robot mode guns. There's a 5mm hole on the back of the flat bed witha pair of tabs down each side, this matches the holes that the guns have been inserted into and the 5mm pegs with slots down the sides that form the handles.
To transform: remove the trailer hitch/guns. Fold the lower legs, formed from the flatbed, waist & upper legs, which are hidden inside the cab, down under the cab and fold his feet out. Again they're grey when maybe they should have been another colour, in this case blue. Customisers will have a field day touching this toy up! Fold the blue panel down onto his bottom. Pull the bottom of rear sides of the cab away and fold forward, then split the front of the cab down the windows. Pull out to the sides to form the arms rotating the arm round at the bicep so the wheels and side panel are on the outer edge of each arm and facing forward. Fold his head out of the top of the cab, the panel with the Autobot symbol on swings from side to side around a central pivot, and place a gun in each hand.
This Optimus is a bulky robot with large forearms somewhat reminiscent of Combat Hero Optimus Prime, thought sadly without the lightpipe feature that toy had. The panels on the side of the arms are inevitable reminiscent of Classics Prime but they work a lot better here almost forming a unit with the rest of the arm surrounding the cab's front wheels inside the forearm. If you'd like a thinner Optimus arm then fold the panels down under the arm: it presents a better profile from the front but looks a little odd when you raise the arms. The proportions look a little odd with the arms seeming too long, most of which is down to the grill of the cab forming the upper arm, but the legs and especially the body are a little too short too adding to the problem. No one piece is 100% to blame here but the result is the hands are around the level of his knees when his arms are hanging straight down instead of being around up/mid thigh level.
Articulation is good: the head turns, the shoulders turn and the arms can be raised to the sides. There's a bicep swivel and a bending elbow on each arm but nothing at the wrist, save for some upwards movement as part of a transformation we'll come to shortly. He has a waist, a universal joint at each hip, a thigh swivel and a bending knee as well as a bending ankle as part of the transformation. It's OK, but you feel a Voyager should have wrists swivels.
He comes with two guns, reminiscent of Powermaster Prime but in this case they're not identical. One picks up many design queues from the original Optimus gun including the butt and barrel while adding extra detail such as a 5mm peg hole on the top and another in the end of the barrel. The second gun, a new design, also has a 5mm peg hole on the top and a 5mm peg sticking out the back. Both have long 5mm handles, necessary to reach he peg hole in his fist and take into account the drop between the top of the arm and the top of the fist. Awkwardly they expose that the guns are made of red plastic instead of the black they're coloured: why not just cast them in black plastic? Sensing that the longer handles may be prone to snappin Hasbro has had a metal pin run up the centre of them to strengthen them, a step also applied to Prime's exhaust pipes behind the cab.
As a toy by itself Prime homages a lot of earlier designs but is subject to a few criticisms. But we're not done yet. Oh no.
To transform Optimus Prime into Ultra Prime's torso mode rotate each arm out to the sides at the bicep joint and turn till they face backwards. Bend each arm back at each elbow so what was the outside halves in robot mode are facing each other and are pointing upwards along what was the robot's front. In this position they slot and tab into place. Fold the hands up to expose the shoulder combination sockets. Fold each leg out to the side at the hips each at about a 45 degree angle to where they usually are. Rotate the thigh swivel 90 degrees so what was the inside of the leg faces fowards. Rotate the waist 180 degrees so the insides of the legs, where the grey panels are, are on the same side as what was the robot's back, which is now the combined robot front. Bend the knees so that the lower legs aproximately point straight down, but are actually slightly pointing toward each toher. Fold the grey panels up so the slots on the front of them meet the tabs on the upper legs locking the robot's knee joint in position. Fold the robot head down. Open the chest. Swing up the combined robot head bringing the grey panel it's attached to up to form thebase of the neck aand the top of the chest. Close the chest doors.
Slide Combiner wars deluxe limbs in to the sockets on the front of the legs and the tops of the arms. Peg Prime's guns together and place into the 5mm peg hole on either of the combined robot's hands.
Given that we're attaching all sort of other robots as limbs, the body needs to scream Optimus loudly to get over what this toy is. The head is definitely Prime with ear antenae so huge they beat even the previous winner, the much derided Optimus Maximus. The chest is red with larger blue windows so I's say we've got the basic details covered here. Like the smaller robot Optimus' comibined robot look is also reminiscent of other toys, with the chest reminding me of both God Ginrai and Star Convoy.
The chest itself opens up, revealing a matrix detail inspired by the Movie scene and copied on many other toys but here it's especially reminiscent of Energon Optimus Prime. Bellow it are two 5mm pegs in a 3 pronged cross shape which presumably allow Blackjack to be attached in the Menasor version of the toy. I'd lay money on that Blackjack getting a blue repaint as Roller for Optimus. In the meantime it leaves Optimus with Nipple attachment points, which guarantees him an entry into the X-rated Transformers pantheon, and I'm sure we'll soon seen picture with all manner of transformers Minicons/Microns attached. With some ingenuity several of the other Legends figures can also be attached as chest plates
Most of his articulation has been locked off for the combined mode torso but you can still turn the waist and head and have full use of the hips. Shoulder, bicep, elbow, wrist, knee and ankle articulation is provided by whichever limbs you've used and is the same on the selection of limbs I currently have: For a combined robot that's decent articulation.
I'm not so keen on the bent back fist sitting on the shoulders of the toy but it's not the first time this has happened with a combined toy: depending on how you position him Abominus has the same problem. Since the hands have the 5mm peg hole at the bottom facing up you might as well use them and raid your 5mm peg weapons box to tool Prime up with some shoulder cannons.
I've seen a lot of people saying "this is just a retooled Motormaster" and "why is there an Optimus Prime in the Combiner Wars line?". I like this toy. A lot. It does something new with Optimus we've not seen before. It challenges the established combiners play pattern by making a torso with no official robots that combine with him, you just attach any toy you want, but there's a lot of people out there not coping well with this idea at all who are fixed that A + B + C + D + E = Z in combiner terms. Personally I'd have been happy with an entire line of toys like this. EVERY Deluxe and Voyager is a combiner component and you put them together however you want, but I can see that being a step waaaaaay too far for many old school Transformers fans. Interestingly the coverage at SDCC boasted "16 deluxe and 6 Voyagers for 2015" which means that there's FOUR teams of four Deluxe limbs plus a Voyager body plus two extra Voyagers. Optimus is one, who's the other? We suspect that the other two team Voyagers are Hotspot and Onslaught and they might share a mould so possibly the sixth Voyager will be a Silverbolt repaint? Personally I think Hasbro may have shot themselves in the foot by doing a 2015 Megatron Tank as a Leader: I'd have loved a Megatron tank combining core and you could easily have got a Bludgeon repaint out of it. Of course if Hotspot is his traditional blue they could repaint that in red as a Fire Engine Optimus in homage to Robots in Disguise Optimus Prime/Car Robots Super Fire Convoy.
Optimus isn't without his faults: The stickers on the shoulders on mine are slightly lopsided. Being unable to position the legs pointing straight down is a problem in combined mode: you're having to position them slightly pointing in and relying on the lower legs touching each other keeping the legs the correct distance apart which in turn places the thigh plates under an amount of tension and causes them to pop off if you move it. That in turn affects the combined toy's balance: please don't get me wrong, it's got pretty decent balance, but Superion's is so much better: I had Superion stood on the desk, with 2013 Legends Optimus stood on Superion's shoulders, I was shaking the desk and Superion wasn't falling over. There's several pieces here that I'd have a different colour: Combined neck plate & matrix and front window panels should be red, not grey, fists & feet should be cast in blue plastic and guns in black plastic.
Voyager figure: Very good, much much better than people thought it would be. Combined figure: decent but Superion is so much better!
Future Repaints and Add OnsAlready slated to be remoulded as Motormaster I see no reason why this toy shouldn't return again as Ultra Magnus (is a repaint of this toy at the heart of the much rumoured Leader Magnus?) and Scourge. The Motormaster remould could be redone as his unreleased Generation 2 variant, recently glimpsed at auction.
As I said above I'd lay money on Menasor's Blackjack being repainted in blue as Roller for this toy.
I had said I wouldn't be surprised to see some of the Combiner Wars limb bots being repainted as 1984/5 Autobots to accompany Optimus, with Dragstrip as Mirage is an obvious one, and sure enough Wal*Mart's computer has leaked the names of four toys that look like they fit this bill: Mirage, Sunstreaker, Ironhide & Prowl
Energon Optimus Prime offers some intriguing possibilities: We've already got a Helicopter limb in Alpha Bravo, how about making Fire Engine, Sub & Drill Tank limbs to homage Energon Optimus? The Drill Tank could almost certainly be reused as Nosecone and Drillhorn as well as effectively being an upgrade for Rescue Force Mole. A new version of Energon Wing Sabre would go nicely with this toy too.
Cybertron could give us Leobreaker which would be a useful mould if Hasbro went down the Predaking route with this combiner system and I see no reason why they shouldn't.
There's plenty of scope for doing things with this Optimus for some while yet. If Hasbro don't I can see third party companies eagerly stepping in.