Do you get advantage on Steel Wind Strike’s attacks because you “vanish”?

The spell steel wind strike says that you

vanish to strike like the wind.

(Emphasis added)

At first glance you might read this as an inconsequential part of the description. But strictly speaking there is no flavour text in spell descriptions. Vanishing implies being unseen, which (if we carry on the logic) grants advantage on attacks due to being unseen.

I’ve seen this argument appear in a couple of answers recently and thought it deserved a question of its own.

However, steel wind strike looks like a pretty strong spell without advantage, and granting advantage on all the attacks seems like something too important to leave to a bit of rules lawyering, which makes be doubt this interpretation.

Do you intrinsically gain advantage on all of steel wind strike‘s attacks?

How can I design a magical weapon that grants an advantage against fire-base creatures without using water and choking effects?

The party I am DM’ing is going for an adventure to the Elemental Plane of Fire. I want to design a magical weapon that can grant an advantage against fire-based creatures. I see that Fire Elementals have Water Susceptibility (Cold Damage) but I have already house-ruled that elemental planes can not include magical effects of elements from other elemental planes, but just the spells that have elements of the current plane can be cast (as the plane purely consists of element of itself). For example, in the Elemental Plane of Air, not only Earth-based spells but all the spells are impeded, except air-based ones.

After I realized that I can’t use a magical weapon that has cold damage due to my house-rule, I wanted to give the weapon a "heavy smoke" effect to choke the fire, as I thought that fire can not live without oxygen. But this option conflicts with my house-rule, also I saw that the fire-based creatures any other fire source in the Elemental Plane of Fire don’t need air to live.

Now I have no idea how can I design a magical weapon that gives an advantage against fire-based creatures without cold damage and choking the fire via leaving without oxygen is not an option. I can not cancel my house-ruling because of the sake of my setting. I am open to any house ruling ideas beside the official ruling.

TLDR: as in title, how can I design a magical weapon that grants an advantage against fire-base creatures without using water and choking effects?

If the question shows up to be opinion-based, please accept my apologies.

Mechanically speaking what makes a item more useful, a raw bonus or advantage? [duplicate]

I’m looking at D&D 5e to homebrew a specific item and I’m debating what would be better. Advantage or raw bonus. The item is a coin that you toss it before a ability check or a attack roll. If the coin lands on the heads, you gain a boon. If the coin lands on the tails, you get a penalty.

I was considering making the boon a raw bonus of +3 to the subsequent roll if it’s a boon or -3 if it is a penalty. But it was brought to my attention that giving advantage/disadvantage could potentially be more balanced. So here’s my question, what would be better mechanically for the player?

Does a player wielding whip gain advantage if it is 10 feet away from the target?

We had an episode in combat tonight that I was not sure how to adjudicate.

A player character (PC1) with a whip was 10 feet away from an enemy.

In between PC1 and the enemy was another player character (PC2) that was prone.

On the far side of the enemy was a third player character (PC3).

Does PC1 have advantage in attacking the enemy with the whip? Why or why not?

If PC2 stands, can PC1 still attack the enemy using the whip, and would this affect advantage in any way?

Does the feat War Caster give you advantage on a constitution saving throw made because of Sleet Storm?

One of the benefits of War Caster is:

You have advantage on Constitution saving throws that you make to maintain your concentration on a spell when you take damage.

The spell Sleet Storm doesn’t deal damage, but the game designers still wanted it to make characters in the AOE make a CON save to keep Concentration. So it states:

If a creature is concentrating in the spell’s area, the creature must make a successful Constitution saving throw against your spell save DC or lose Concentration.

I definitely don’t think this is an intended interaction, but RAW, shouldn’t War Caster be useless for this since it says "when you take damage", and Sleet Storm is not a damage dealing spell?