Games like MDK
Games like MDK include STAR WARS™ Battlefront II (Classic, 2005), HELLDIVERS™ 2, Half-Life, Half-Life 2, and Grand Theft Auto V Legacy. We matched them by the tags players give MDK on Steam (Action, Classic, Third-Person Shooter, Sci-fi, and Third Person): closest matches first, and among equally close ones the better-known games.

STAR WARS™ Battlefront II (Classic, 2005)
Shared: Action · Classic · Third-Person Shooter

HELLDIVERS™ 2
Shared: Third-Person Shooter · Action · Sci-fi

Half-Life
Shared: Classic · Sci-fi · 1990's

Half-Life 2
Shared: Action · Classic · Sci-fi

Grand Theft Auto V Legacy
Shared: Action · Third Person · Third-Person Shooter

Half-Life: Opposing Force
Shared: Action · Classic · Sci-fi

STAR WARS™ Jedi Knight - Jedi Academy™
Shared: Action · Sci-fi · Classic

Warhammer 40,000: Space Marine - Anniversary Edition
Shared: Action · Third-Person Shooter · Sci-fi

STAR WARS™ Battlefront™ II
Shared: Third-Person Shooter · Action · Sci-fi

Black Mesa
Shared: Action · Sci-fi · Classic

Vanquish
Shared: Action · Third-Person Shooter · Sci-fi

STAR WARS™ Jedi Knight II - Jedi Outcast™
Shared: Action · Classic · Sci-fi

Halo: The Master Chief Collection
Shared: Classic · Sci-fi · Great Soundtrack

STAR WARS™ Battlefront (Classic, 2004)
Shared: Action · Classic · Third-Person Shooter

Hitman: Blood Money
Shared: Action · Classic · Third Person

Max Payne 2: The Fall of Max Payne
Shared: Action · Third-Person Shooter · Classic

Resident Evil 4 (2005)
Shared: Action · Third-Person Shooter · Classic

Half-Life: Blue Shift
Shared: Action · Sci-fi · Classic

Quake II
Shared: Classic · Action · Sci-fi

Mafia II (Classic)
Shared: Action · Third-Person Shooter · Third Person

Max Payne 3
Shared: Action · Third-Person Shooter · Third Person

Bully: Scholarship Edition
Shared: Action · Third Person · Classic

Max Payne
Shared: Action · Classic · Third-Person Shooter

Warhammer 40,000: Space Marine 2
Shared: Action · Third-Person Shooter · Third Person