Chopster's robot mode - for it's easiest to start here - is mainly clear orange with black arms and upper legs. Both colours are found on Smoulder so I guess they're gang moulded together which reduces the chances of Minicon (or Minicon/Drone Limb) multipacks. Boooo ! The shoulder & hips are ball joints with the knees bending. He's got one Minicon socket on his chest and a gun running up his back attached to a hinge on his bottom - bend it down and use is as a tail! His arms are shaped like 4 barrelled gatling guns giving him some weapons in robot mode.
Chopster transforms into a cannon for Smoulder's vehicle mode: Turn so he's chest side down. Fold both arms forward, so they and the gun up the robot's back are pointing in the same direction as the head. Fold the lower legs back so they cover the upper legs then fold all 3 barrels so they face away from the head. Peg onto Smoulder via his vehicle mode Minicon peg on his roof. You assume Chopster's a water cannon due to Smoulder being a fire truck but he might just be a flame thrower if Smoulder belongs to the sort of fireman seen in Fahrenheit 451. Given that he's a Decepticon this seems likely ! This weapon can also be used as a Handgun is you insert a Lego Technic connector into the Mini-con socket and let the robot hold the other end of the connector.
Chopster also forms a different hand held weapon for Smoulder. From robot mode fold down the gun barrel down the robot's back. Fold the arms down straight so the ends are behind the robot's hips. Bend the legs forward at the hips, fold to the sides at the hips and then turn each leg 180 degrees at the hips so the blades on the front of the legs face down. Bend the legs at the knees so what was the heels touches the tops of the robot chest. This axe mode can be held by it's handle by any toy with a 5mm peg hole right the way through their fist - the points of contact are a couple of rings mounted a little way (4mm) up the axe's shaft. As a bonus this mode also makes a passable jet plane !
Finally Chopster also form body armour for Smoulder. Without instructions I can't say exactly what it should be but it would seem to be some variation on the axe mode attached to Smoulder's chest peg. He looks silly with the handle/gun barrel up by his face obscuring it so it has to be the other way up. Which means the handle/gun barrel - which is on a hinge - ends up at waist level. Whichever way it gets bent - down, up or sticking out - it looks like male genitalia after that !
Decent robot, gun & axe modes. The chest armour is a tad dodgy but that's not bad for a toy of this size.
I planned not to buy one at Import prices due to Darkstream being a poor repaint, a poor mould to start with and a poor pairing for Chopster's repaint. As the mould stands he can't hold the axe mode due to a lack of depth in his fist and he can't use the chest armour due to no peg there. Poor show Hasbro. However Kapow Toys had all of then repaint wave of Powercore in at UK prices. So I was duty bound to relieve them of a set. Opening the instructions up reveals that they think Razorbeam can be held in axe mode by Darkstream - he can't, I've tried it, he's moulded the same as the original. You'll have to settle for using Darkray as a gun and pulling the Lego Technic conmnector trick described above.
Chopster's partner, Smolder, is coloured white and packed with two Combaticon and two Aerialbot recolours to form the Protectobts.