Killzone HD

Killzone is a first-person shooter, developed by Netherlands-based Guerrilla Games and released on November 2, 2004 in North America. Killzone takes place in the middle of the 24th century and chronicles the war between two human factions; the Vektans, and the Helghan. The game is played from a first-person view and follows Jan Templar, a high-ranking officer within the Interplanetary Strategic Alliance, as he battles invading Helghan forces into Vekta.

I played this game on medium difficulty and completed at least one mission with each character. The controls and gameplay in this title are a bit dated but the experience is enjoyable overall.
There aren't that many changes from the PS2 version, only HD resolution and some fixes here and there.