A great example of this is the box art for Metal Gear Solid V: The Definitive Experience.
I've seen it sometimes used on movie and video game covers, but never knew the name of it.
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Images of this style often appear in advertisment, Propaganda and to some degree religion. Basically this style is employed to promote an Idea or a Person. You might want to look at Keywords like 'Heroic Realism' 'Social Realism' which describe the style of Painting employed in 20th century Dictatorships - especially for propaganda (search phrases 'Soviet Propaganda', 'Heroic Realism propaganda')
Early examples of this style appear already frequently in Religious paintings of the early and high middle ages and can be found in every epoch.
However, I think it is not possible to name a specific style of paintings as what you are looking for is more of a compositional technique to highlight the importance or power of something or someone.