What are the implications of the Find Familiar and Find Steed spells changing the creature type from Beast to Celestial/Fiend/Fey?

The Find Familiar and Find Steed spells both have this sentence describing the creature type of the summoned creature:

The [familiar/steed] has the statistics of the chosen form, though it is a celestial, fey, or fiend (your choice) instead of its normal type. (PHB 240)

I’m wondering what implication choosing celestial vs. fey vs. fiend for the summoned creature would have. I have three things I’m specifically interested in listed below.

  1. Is a familiar visible distinguishable as the type of spirit? For example:
    • A wizard with an allergy to cats conjures a hypoallergenic fey cat sprouting soft grass instead of fur
    • A tiefling paladin conjures a fiend warhorse steed to have a coat colour resembling a Nightmare
  2. Does the type have any effect on the familiar’s alignment? For example:
    • Inheriting the alignment from the creature’s stat block (unaligned in most cases) seems like the most direct option but would a celestial imp still be considered lawful evil?
    • If you command your fiend cat to sit on someone it may choose to painfully knead them whereas a celestial may be more relaxed and cuddly.
  3. Does changing a familiar to a new form allow it to change the type of spirit?

    If you cast this spell while you already have a familiar, you instead cause it to adopt a new form. Choose one of the forms from the above list. Your familiar transforms into the chosen creature.

    Adopting a new form sounds like it remains the same kind of entity. Does this mean to change the familiar from fiend to fey would require summoning a new spirit and therefore be treated like a new NPC?

These are grey areas in the rules, I am looking for official guidelines or other credible sources that can help me make an informed decision on how to rules these as a DM.

Under what circumstances does a phantom steed take a minute to disappear

Phantom Steed
3rd level illusion
Casting Time: 1 minute
Range: 30 feet
Components: V S
Duration: 1 hour
Classes: Wizard
A Large quasi-real, horselike creature appears on the ground in an unoccupied space of your choice within range. You decide the creature’s appearance, but it is equipped with a saddle, bit, and bridle. Any of the equipment created by the spell vanishes in a puff of smoke if it is carried more than 10 feet away from the steed. For the duration, you or a creature you choose can ride the steed. The creature uses the statistics for a riding horse, except it has a speed of 100 feet and can travel 10 miles in an hour, or 13 miles at a fast pace. When the spell ends, the steed gradually fades, giving the rider 1 minute to dismount. The spell ends if you use an action to dismiss it or if the steed takes any damage.

Looking at the wording of this spell, it appears that because “when the spell ends, the steed gradually fades” and “the spell ends if you use an action to dismiss it or if the steed takes any damage,” is it correct to interpret this as meaning that even if a steed is attacked in combat, it is still a fully-functional mount for the next minute?

If so, to what extent does this apply? Would a steed targeted by Dispel Magic or one inside an Antimagic Field also take a minute to fade away as the spell ends? Is there any circumstance in which it would immediately disappear?

How does Phantom Steed behave in combat?

The description of the 3th level Wizard ritual spell Phantom Steed reads:

The creature uses the statistics for a riding horse, except it has a speed of 100 feet and can travel 10 miles in an hour, or 13 miles at a fast pace. When the spell ends, the steed gradually fades, giving the rider 1 minute to dismount. The spell ends if you use an action to dismiss it or if the steed takes any damage.

I’m unclear on how Phantom Steed behaves, especially in combat:

  1. If the steed takes enough damage to be killed, does it die immediately or does it continue existing for 1 minute?
  2. Can the steed perform the dodge, disengage, or dash actions as a regular mount can?
  3. Can the steed pull a wagon or other vehicles?
  4. If not ridden, does the steed block the space it is on? If not, is the space it occupies considered difficult terrain?

While riding a mount summoned by Find Steed, when does the caster choose whether the mount is controlled or independent?

Other Q&As on RPG.SE have discussed the by-now-familiar rules for mounted combat, including the differences between controlled and independent mounts. See, e.g., When can you choose to control a mount? Mounts summoned via find steed, however, are a special case. Per this 2018 guidance from Jeremy Crawford,

when you ride the mount [summoned via find steed] in combat, you decide whether it follows the rules for a controlled or an independent mount.

What remains unclear, however, is precisely when a caster who is already mounted on the summoned steed may, or must, make that choice. For example, it could be:

  • When the DM calls for initiative rolls.
  • Only on the caster’s first turn.
  • Only the mount’s first turn.
  • On any turn the caster takes.
  • On any turn the mount takes.
  • On any turn whatsoever.

Some of these options would require the caster to choose only once and stick with it. Others would conceivably let the caster change her mind each round, or even multiple times each round. Which (if any) is the correct way to handle mount control using find steed?

Do steeds summoned with Find Greater Steed have other options than the usual control rules during mounted combat?

During mounted combat, I understand there are two possible options:

  1. You can control your mount, in which case your mount cannot make an attack, or
  2. You can opt to leave it independent (and controlled by the DM) in which case it can attack, but may do things you don’t expect.

The text of find greater steed contains this excerpt:

Your steed serves you as a mount, both in combat and out, and you have an instinctive bond with it that allows you to fight as a seamless unit.

Does this phrase imply that there is some special way to control the steed beyond the above two normal options for mounts? Are steeds summoned in this way special in regards to the control rules, or is that just flavor text? It seems to me that an independent mount which can take actions that I cannot predict is not fighting as a seamless unit with me. Am I misunderstanding something?

The question here certainly provides an answer, but it’s not satisfying since it assumes that the mount has to use one of the two above options and does not consider that there may be alternatives.

Does a familiar/steed/greater steed keep its memories between recasts of its find spell?

When questioned about polymorph Crawford offered:

A spell doesn’t erase/suppress your memories unless the spell’s text says it does.

When the text of a spell, like polymorph, says you retain your personality after a transformation, that’s a terse way of saying, “You’re still you, despite the radical changes you undergo.” #DnD

However the first and second statement seem to contradict each other for find spells. None of them say the spirit’s memories are erased/suppressed. But they also don’t say they retain their personality, which in the context of his tweet is how creatures remain themselves between transformations.

Is the “Find Greater Steed” Spell affected by Barovian Magic Alterations?

So, in Curse of Strahd there’s this thing called “Alterations to magic” which causes spells to take an evil turn. For instance, a wizard casting Mage Hand will find himself with an skeletal hand instead of a normal one, or maybe he will find his familiar to be undead and so on.
Same thing happens for the Paladin spell Find Steed:

Find Steed. The summoned steed is undead—not a celestial, fey, or fiend—and is immune to features that turn undead.

I’m currently running a Curse of Strahd campaign in which I’m letting my players use Xanathar’s Guide to Everything spells, one of them being “Find Greater Steed”. Curse of Strahd doesn’t have any alterations or notes regarding the spells in Xanathar’s Guide. Is Find Greater Steed affected the same way as Find Steed is?

Can you copy a Tiny Hut spell onto a Medium-sized mount from the Find Steed spell?

Tiny hut is a “self”-target spell that allows the target (typically one’s self) to exist in the hut with up to 9 other Medium creatures.

Find steed allows spells that only target yourself to be copied to the steed (while you’re mounting it).

Tiny hut fails if a creature larger than Medium is inside. But if the PC is Small, and their mount is Medium, would this work?

What’s the difference between the Find Steed and Find Greater Steed spells?

What’s the difference between the find steed and find greater steed spells?

I found the find steed and find greater steed spells while playing 5e. By the rules as written, they seem almost identical except for the spell level and what they have listed as an example for the creature summoned. Is that the only difference, or is there something I’m missing?