Please give some clarity for Master's Summons ability

[Vesterbro]

Ability description: Heal your companion and call it to your side.
But it doesn't cover all companion, eh?
It only works on Kubrow, Kavat, Helminth Charger, MOA (Companion), Predasite, and Vulpaphyla

What about this then

 

Is Helios and other sentinels, companion or not?
I know that you mean companion as in kubrow kavat etc
But if this mod set are for companion, and animal instinct too usable by both sentinel and beast companion, so why not the ability works for sentinel?

If you really meant that this ability not working for sentinel, take a look at its wording.
Suggestion: Add some additional description like: Heal your beast companion and call it to your side.

[SpicyDinosaur]

because your sentinel doesn't wander off? This seems like a you problem. If you want to heal your sentinel you can just as easily drop a health pizza.

[Vesterbro]

I know that already, I'm pointing out the wording bruh
 

[(PSN)Onder6099]

Works on Sentinels.

[Vesterbro]

ok gotcha, seems like I was under wrong impression about this skill

[_AlanT_]

i was hoping it would REVIVE your companion (being sentinels also) and when i found out it didnt ive not used it since.

the ability takes up an entire other warframe ability, in my opinon its one of the weakest from the new system.

when it could of been on par with the rest.

[Graavarg]

"Clarity" has occasionally been a bit fudgy concerning "companions" (especially with different mods and their effects), though DE has remedied most of them and there is now a mostly clear taxonomy.

AFAIK "companions" is now the "superclass" that covers everything (which answers your question), and there are defined subdivisions. All companions are split into "robotics" and "beasts":

• The "Robotics" class is subdivided into:
  • "moas" (4)
  • "sentinels" (9)

• The "Beasts" class is subdivided into:
  • "kubrows" (9), which is divided into:
    • (real) kubrows (5)
    • helminth chargers (1)
    • predasites (3)
  • "kavats" (6), which is divided into:
    • (real) kavats (3)
    • vulpaphylas (3)

Some sentinels also have primed variants, and Shade has a Prisma Shade variant.

A commonly used term is "pets", which nobody is exactly sure about anymore (but probably should be considered equivalent to "beasts").