Enemies in Warframe scale to an incredibly high level, up to level 9999 (except for Eximus enemies), but weapons and Warframes are limited by the mods you shove in them. So this means you need to find more ways to do damage to enemies, as their health and more importantly their armour scale to insane numbers.
So we have two options. Critical damage and Elemental or Status damage.
Critical damage is simple. Every weapon has a critical chance and a critical damage multiplier, which defines how much damage you do when you get a random crit or when you score a headshot. There are only a few mods that affect these stats, and the majority of weapons can only get a set amount of critical damage and chance without resorting to a Riven mod.
Status Chance refers to the chance of an attack doing an elemental effect, based on what elements you have on your weapon. This applies to all elements, not just your heat, toxin, cold, electric and combo elements, but to the physical damage of Impact, Puncture and Slash as well. Each effect has a specific ability, like Toxin directly damaging health, Magnetic removing 75% of shields and Corrosive removing 25% of armour. Slash is the most popular as it deals direct damage to health while ignoring armour, and Corrosive generally rubs salt into the wound.
The difference with both Status and Critical damage is that they only do as much damage as your weapons do.
Most of the time.
Critical Damage is by far the better scaling damage, but only on melee weapons. Blood Rush increases your critical chance, based on your melee combo. As your melee combo increases, you gain a multiplier and do more critical damage. There are mods like Drifting Contact that increase the time you have to keep the combo going, and combined with your critical damage mod Organ Shatter and the 90% critical chance on slide attacks produced by Maiming Strike mean you can use spin attacks to kill for a long time. Not forever, but for a while.
Guns though, they don’t get any mods like that. You either score headshots or get 100% critical chance and as high a critical damage multiplier as possible with mods and that’s it.
So does Status Damage compare? Not really. It doesn’t have the same scaling damage that Critical Damage does, not even with melee.
But status melee does try though, thanks to Condition Overload.
You see, Condition Overload does 60% more damage for each status effect on a melee weapon. You can also use primary weapons to add even more status effects. Theoretically, you can get a lot of damage, since this includes Impact, Puncture and Slash, plus your status effects. Most normal weapons, you can get two elemental status effects, generally elemental combos like Corrosive and Blast, Viral and Radiation and Gas and Magnetic. You can combine this with another combination of elements on a primary or secondary weapon. Some weapons have innate elemental damage, like the Dark Dagger or Zenistar, have an element built in, giving you more damage. Weapons like the Lesion, which has extra Toxin damage, and Zaws made with the Plague Kripath or Keewar, which have extra Viral damage, work even better with Condition Overload. A popular combo is the Zakti secondary weapon paired with a thrown melee weapon with Condition Overload, which can give you a total of five or even six elements, giving you a huge damage boost.
But due to the limited number of elements, even Condition Overload can go so far. At the end of the day though, you want to do damage to enemies past level 300 or so and not have to rely solely on Warframe abilities, you might want to use a combination of both elemental and critical damage.
The real winner though is Corrosive Projection. This aura mod reduces armour by 24%. If you get a squad of four using this aura, you can get 96% armour reduction. This is key to a huge number of marathon runs, because armour can scale so sharply. But that 4% remaining armour can still give enemies a huge amount of hitpoints that you need to deal with. So you’ll need a bunch of Coaction Drift mods, which increase the effectiveness of your aura mods, to get those last few numbers.
Most people aren’t fighting level 300 enemies though. Heck, the only places these even exist are in endless missions, and even then, outside of Elite Sanctuary Onslaught, you don’t see enemies that high until after about an hour and a half of playing. If you’re just going through the star chart though, you can do whatever you want.