Scorponok's personality seems to have two main features: He's dumb, and he's loyal to Megatron (surprisingly so, considering Megatron's other crew members), and of those two features, only the loyalty seems to be consistent. He tries to serve Megatron to the best of his abilities, but when Waspinator is able to outwit you, there's only so much you have to offer.
Scorponok begins as Megatron's second-in-command on the Darksyde, though he is insecure about the title and constantly tries to assert himself among the other Predacons who, aware of his shortcomings, generally dismiss or ignore him.
Scorponok's only other real contribution to Megatron's cause is in developing cyber-viruses that he delivers with his cyberbee drone. (This is impressive, actually, given his otherwise limited mentality.) However, these generally don't work out as he hoped, and so they've done little to increase his standing in the eyes of the other Predacons.
The Predacon that would be called Scorponok and a guy called Backslash were part of a mission to steal the sacred Maximal relic, the Golden Disk, on behalf of Cryotek; in actual fact, "Scorponok" was loyal to Megatron and in on his plan to take the disk for himself. He was meant to bomb a power plant to aid Megatron and his partner's attack; he was almost caught by a guard but Backslash saved him, berating him for being sloppy. Later on, when Backslash was caught by a guard, "Scorponok" laughed and happily triggered the bombs, killing his alleged comrade. Nice guy.
With the Disk in their hands, the thieves were picked up by their other comrades in a stolen ship, newly christened the Darksyde. Soon after leaving Cybertron, the Darksyde was involved in a space battle with the Maximal vessels Axalon and Chromia 10 and an unidentified Predacon ship. At its conclusion, only the Axalon and the Darksyde survived, and both ships passed through a transwarp portal to an unknown destination.
Crash-landing on an unknown planet, Scorponok and his peers were forced to take on organic beast modes to shield themselves from the planet's dangerous levels of raw energon. Scorponok now transformed into an organic scorpion. When Dinobot furiously berated Megatron for foolishly marooning them on the wrong planet and attempted to attack his leader, Scorponok stood behind Megatron and waited for his cue to fire on Dinobot, sending the traitor far into the distance. Later, Scorponok participated in the first battle between the Maximal and Predacon factions and managed to trap Cheetor's leg under a boulder. However, the Predacons soon succumbed to energon overload.
After recovering in beast mode, Scorponok and the lower-ranking Predacons were wagering who would win the battle between Optimus Primal and Dinobot until Megatron ordered them to fire on the unwitting combatants. After their shots failed to destroy the Maximals but instead revealed a massive energon cache buried inside a mountain, the Predacons moved out, followed by the Maximals. The two parties confronted each other at the energon cache, and Scorponok fought Dinobot in the one-on-one clashes that ensued.
Later, Megatron tasked Scorponok with a mission to create a virus for his cyberbee that would turn Optimus Primal into a coward. Ambushing the Maximal leader and Dinobot as they were on a botanical study near a waterfall, Scorponok managed to have his cyberbee latch onto Optimus when he attempted to help the traitor. Unfortunately, Optimus Primal fired off a shot before going down, dislodging the log Scorponok was sitting upon and sending him over the edge of the waterfall. To greater misfortune, Scorponok had botched the virus, turning Optimus Primal not into a coward, but a fearless, ultra-aggressive berserker. Both Scorponok and Megatron were blown up with the cyberbee when Primal ripped it off and chucked it at Megatron's back. Other than this, Scorponok's major contributions to the Predacons were all related to the fact that he possessed nothing but heavy artillery for weapons. Sadly for Scorponok, the actual value of any shots he fired was limited with more or less a single exception: when he blinded the Maximals by detonating an energon deposit.
Although he rarely did anything of importance, Scorponok once fought Dinobot one-on-one and gave a very good account of himself. When the Maximals invaded the Darksyde to retrieve their comrade Rhinox, Scorponok not only held his own, but dominated the fight, up until the point where Dinobot used his rotary blade weapon to win. This is even more impressive when one takes into account he'd already gone a few rounds with the smirker Terrorsaur just prior.
After learning of Optimus Primal's destruction, Scorponok laughed along with his fellow Predacons, then congratulated Megatron, but was pushed away by his leader. Scorponok died along with Terrorsaur when the two, affected by the transwarp wave that turned Megatron into a Transmetal, crashed their hover platforms into each other and tumbled into the lava beneath the Predacon base during the explosion of the Vok's artificial moon. No one much noticed, though Blackarachnia pointed out that only Waspinator was present with Megatron when the Predacons arrived at the Axalon (only to keep herself from getting blasted).
Scorponok is playable for the Predacon story mode. However, unlike the beefy rockets he cannons from his claws in the series, in the game, he fires an incredibly unimpressive stream of little green bolts, giving him low firepower. Like the rest of the characters in the game, his voice bears very little similarity to what he sounds like in the TV series, sounding more like a little girl with a cold.
In Maximal story mode, Scorponok is the boss for the Desert stages. The bout starts with him standing outside his base (yep, his own personal base), protected by a shield and complete with two autoguns (he'd been saving up for his own little place in the wasteland, obviously), on the opposite side of a canyon from the Maximal. Whilst the autoguns fire, he also unleashes volleys of his "almighty" green bolts. Once the guns are destroyed, the whole shield program shuts down. Scorponok then begins strafing and firing, but after a few more hits, he falls into the canyon. However, the guy isn't finished yet. The next stage starts with the Maximal jumping into the canyon and battling Scorponok close up. The two still fire at each other with guns, though, as the game has no melee. However, Scorponok boasts an unexpected advantage in this fight: He is quite short, meaning that if you're playing a taller character, sometimes the only easy way to hit him is to jump over the Predacon's head and shoot him. After a few more blasts, Scorponok collapses (and presumably the Maximal loots his base).