Naughty Dog is one of the best PlayStation exclusive developers when it comes to pushing the limits of PlayStation hardware but they are not without competition. Santa Monica Studio and Guerilla Games are on the same level and push PlayStation hardware as much.
There is a reason why I think so, Naughty Dog themselves have said that they could push PS4 further and PS4 keeps giving each year. Last gen when Naughty Dog released Uncharted 2 people never thought it would be surpassed graphically by another PS3 game but the next year God of War III came and blew away everyone. Santa Monica surpassed even that with Ascension. They have been pushing PlayStation hardware since the PS2 as God of War II was the best looking game on PS2. I think they will create a new benchmark in graphics on PS4 with God of War IV.
Guerilla Games have also made games that pushed the PS3 to its limits with KZ 2 and 3 and KZ 3 may be the most technically impressive game released on PS3. KZ 2 and 3 had quite open ended levels unlike Uncharted and God of War but they still looked as good if not more detailed especially the environments and particle effects. They made KZ: SF that was constrained by a being a launch title for PS4 and yet it is still one of the best looking games of current gen. Horizon footage looks incredible and the Dino bots are highly detailed even with the open world setting. This game will probably set a new bar for open world game visuals on PS4.
