You're assigned to design and create a monument similar to Mt. Rushmore to embody the greatest, most influential idols in gaming. Much like the prime ministers (or whatever Americans call them) carved into Mount Rushmore, what gaming characters embody the core of video gaming and its history best? Note that we're not looking for a "favourites" or a "what characters are YOUR idols" monument... We're talking one that ALL gamers would generally understand (though you can totally do a favourites one for fun in the comments :P).
Me personally, assuming we're limited to four, I'd go with Pac-Man, Mario, Cloud Strife and Master Chief. Pac-Man is the "founding father", if it were - the character that helped solidify gaming as an entertainment mainstay. Mario goes on there for being a "builder", for popularizing the side-scrolling platformer genre and helping bring gaming into the living room. Cloud goes on there for popularizing a genre that shows gaming can be much more than just platformers, but that can instead be massive stories with deep gameplay systems and character arcs. Master Chief goes on there for basically creating online gaming (outside of the PC, anyway), creating a whole new breed of Dorito-eating, Mountain Dew-drinking bro gamers and making gaming a much more social experience than ever before... But I'd be okay if we left the Chief one unfinished. :D