Why do Space Marines have different helmets

[Veles]

Haven't played the game, but Space Marines always had two types of helmet which are tactical marine helmet that has pipes on the side with something like microphone in the middle and assault marine helmet that is usually pointy and has no pipes.
Looking on youtube videos of Space Marines 2 gameplay, I see they have different type of helmet. It's red colour which is odd considering that Ultramrines are Blue and Gold. I assumed maybe Lieutenant have different helmets, but it seems everyone has same type of helmet.
Did I miss something? I remember Space Marines always had same helmet in Dawn of War, Dawn of War 2, Space Marine, and Battlefleet Gothic Armada (Space Marine boarding ship icon had Space Marine and few cutscenes when they were not focus we could see Space Marine with helmet). I am curious if these are maybe different type of Space Marines, Ultramarines have different model or maybe someone just decided to change the model.

[Darth Revan]

the space marines in the game are primaris marines so they have mk x helmets and armor.

also for the ultramarines the fully red helmet is like a badge of honor, the blue helmet with the red/white stripe is a rank marking.

[DeusEstMachina]

Originally posted by Veles:

Haven't played the game, but Space Marines always had two types of helmet which are tactical marine helmet and assault marine helmet that is usually pointy and has no pipes.
Looking on youtube videos of Space Marines 2 gameplay, I see they have different type of helmet. It's red colour which is odd considering thst Ultramrines are Blue and Gold. I assumed maybe Luthenets have different helemts, but it seems everyone has same type of helmet.
Did I miss something? I remember Space Marines always had same helmet in Dawn of War + exapnsions, Dawn of War 2, Space Marine, and Battlefleet Gothic Armada 1 and 2 (only in icon and few cutscenes we could see). I am curious if these are maybe different type of Space Marines, Ultramrines have different model or maybe someone just decided to change the model.

tactical marines in the past (what we call first-born) mainly wore mk7 helmets with the "angry face" vox grille. and so did assault marines.
the beaky helmet you're referring to is the mk6 design. a holdover from an older version of the armor. it's not limited to assault marines, and tactical marines, and any other type of squads wearing power armor could wear it. in model kits for the tabletop game, every squad usually had a full set of mk7 helmets, and one or two mk6 helmets so you could make your squad of warriors look a little more unique.

the red helmet on ultramarines denotes a sergeant. always has. it's just in a lot of illustrations and games, sergeants don't wear helmets, because it's easier to identify who's the "hero" in the squad that way.

the space marines in this game wear the newest armor type that was specificaly designed for primaris space marines, called the mark X Tacticus, which is why they have a new type of helmet - which, incidentally resembles an older variant, the mk4.
there is also a stripped-down, light-weight variant of the Tacticus, called the Phobos-pattern armor, worn by the "vanguard" and "sniper" classes.
There is also a heavy variant, the Gravis pattern armor, which is worn by the "heavy" class.

edit: also, the veteran 1st company of the Ultramarines wear white helmets. squads from the 1st company are often attached to other battle companies, so it's not uncommon to see one or two squads of white helmeted dudes among the larger blue-and-gold force.