Is it legal to use someone else's render of a character in your thumbnail?

[Articaxd]

Can explain my question down here. Found a cool render of a character from a video game, am I allowed to use that rendered character (that the person does not own, just made a render of) and put it in a thumbnail of mine? Might be a stupid question but I'm just now getting into YouTube. I feel like I should be able too because the character isn't owned by the person right? I don't know.

 

[Shakycow]

You're asking if you can use someone else's work without contacting them (or the original copyright holder) or acquiring any of the required rights to do so?