Stalin from Red Alert already has Pure Evil category, but he needs approval.
What's The Work
The work is an RTS game called Command & Conquer: Red Alert.
Who is the Candidate? What They Did?
Joseph Stalin is the main antagonist of the game (or a boss of player character in Soviet campaign) who rules the Soviet Union and invades Europe and China to make it a continental empire. To achieve this goal he uses whatever means necessary up to usage of nuclear and chemical weapons on civilians.
What they did
Started World War 2, the bloodiest conflict in the human history. Numerous war crimes including deployment of Sarin gas against Polish resistance, ordering massacres of Torun and Grunyev revolution with children included, slaughter of various villages during an invasion of Greece with usage of tactical nukes on them and a launch of nuclear missles across Europe (at least at London and Paris), which Allies managed to disable.
Freudian Excuse/Mitigating Factors
None. He is driven purely by his desire to expand the USSR across an entire continent. He has no regard for the lives the war took including the ones of his own people. In the Soviet campaign he at first orders to shoot his best commander for failing to capture the chronosphere and when he found out that Kukov is responsible for this failure he angrily broke the latter's neck. He has no love nor sympathy shown towards anyone and when he started to lose the war against Allies he began lashing out his anger on his subordinates to the point some of them like Vladimir Kosygin decided to defect to the opposing side.
It is safe to say that he stands out from other villains of C&C franchise possibly excluding Yuri, who is nearly as bad as Stalin. Aside from Stalin and Yuri Kane also performed global scale atrocities, but he genuinely believes he is making humanity stronger and unites it this way while Stalin's motives are purely egotistical.
I give a strong yes that Red Alert's Stalin is heinous enough to be PE.