Progression abilities

As I recall, you did have a thread asking us what Shards we wish to see in the game in the past. It's nice to see you revisit this, if only specifically about Progression abilities (whether they're Skill Shards or otherwise).

That said, I shall repost a couple ideas I had in that thread for "Progression" Shards here (slightly modified to reflect certain changes made to gameplay since then):

1.) Trigger Shard: Crystal Sprout
Obtained from: Crystal Golem (BOSS)
Description: REQUIRED to find certain Key Items. A magical crystal grows from the ground directly in front of Miriam at an accelerated rate, which will inflict "Strike" damage to all enemies that come in contact with it. Items or Gold can sometimes be uncovered from beneath floors and other surfaces.
Upgrading: Shard's attack-power can be strengthened depending on total items found with this ability.

2.) Enchant Shard: Blood Magic
Obtained from: Gashadokuro (BOSS)
Description: Grants Miriam the ability to restore her magic reserves (MP) just by hitting enemies that bleed and standing in the blood-spray's path. REQUIRED to defeat certain tough guardian enemies that block your progress (by sapping MP from them, beyond their own limits).
Upgrading: Using this Shard in conjunction with the Shard obtained from Bloodless will sharply raise the amount of MP absorbed from each hit against "bleeding" enemies (the Bloodless Shard needs to be used to hit enemies).

3.) Effective Shard:  Afterimage Strike
Obtained from: Learned after confronting Alfred a second time(?) (Currently unknown whether Miriam will simply talk with him, or fight him, in the story)
Description: Miriam summons a ghostly image of herself just ahead to mimic her movements and damage enemies on-contact. REQUIRED for bypassing seemingly impassable walls & surfaces to activate switches, and solve certain puzzles.
Upgrading: Can be augmented with certain materials to add elemental attributes to the afterimage's mimicry attacks.

4.) Effective Shard: Suspend Momentum
Obtained from: Penanggal (or "Nukekubi"; enemy)
Description: Miriam is now able to hover in one location at any point in a jump or while falling. Miriam can gain "momentum" (extra damage) for her Dive-Kick when using this Shard by staying in position for an extended period of time. REQUIRED to destroy certain floor barriers throughout the Castle.
Upgrading: Collecting more of this same Shard (maximum of 9) will increase the amount of damaging debris created upon impact with surfaces.

5.) Enchant Shard: Sense of Majesty
Obtained from: Abaia (BOSS)
Description: REQUIRED to gain access to all rooms in the underground lake of the Castle (assuming that's an area we get to visit); All aquatic enemies in this specific area become non-hostile (reflecting the Abaia's mythological role as protector of sea creatures) and allow Miriam to pass into otherwise inaccessible areas. Miriam also gains the ability to "see" in dark underwater areas, becoming capable of solving puzzles that were formerly invisible.
Upgrading: In each New Game+ playthrough, absorbing Abaia's Shard again may increase the chance of "aquatic" enemies in other areas of the Castle fighting for Miriam rather than against her.

ADDENDUM: I think that's enough for now. I might come up with some Item/Equipment ideas later.

I like that cloud of glass shards idea from ClearAzure.

I think Miriam should have a Crystal Shard Hand that is an aim-able ability (like the fire ability from the demos) that shoots out a crystalized hand to grab onto special grappling points throughout the world. It is like the whip-swing from SCV4 or the magnet ability from Order of Ecclesia, but would work more like Death's Grip ability from Darksiders 2 (but in 2d/2.5d). You would use it to launch yourself across chasms or vertically to reach very high areas.

Progression, for sure. I bank on at least one whole area that can only be accessed by it. Although, it would be also cool if said area(s) were completely missable.

Enkeria Yeah, I'm hoping there'll be puzzles like that which require manipulating gravity to solve. I'd very much like the "Invert" ability to have actual use beyond simply moving throughout Gebel's Castle. Certain "switches/levers" or other mechanisms should only work in the first place if gravity is flipped; they couldn't function otherwise, and/or will stop working immediately after you activated them, if you return gravity to normal.

I could suggest a gravity puzzle which involves manipulating the momentum generated by Miriam's dive-kick (related to the "Suspend Momentum" Shard idea I posted previously).

I really want a Castlevania IV whip-swinging move where you grapple-swing between points with some level of platforming skill. (Going over a place where, say, a bridge has collapsed.) IGA finally put something like that in Harmony of Despair, so why not here, too?