Ichor of Elpis

Star light, star bright, first star I see tonight...

In desperate times and despairing lands, there is ever and always the chance for hope to prevail. In many ways, this manifests in magic - acts of deific intervention, the manifestation of an avatar's will, or the indomitable inner well of innate power many mages hold within themselves.
But sometimes, hope manifests more literally. In the darkest of nights, the stars still shine, and for those who wish upon them, sometimes the night sky is kind enough to weep. The tears that fall are referred to as the ichor of Elpis, a celestial servant of hope and wishes, and may be captured in lacrimaria to be used to power small wants, wishes, and whims.
If enough of these tears are gathered, the ichor can be pooled to create grand wishes rivalling deific miracles, or can be used as a component in potent spellcasting.

Bottling the Ichor of Elpis by Hanhula (via Midjourney)

Importantly, the gathered wishes used for bigger wishes must have all fallen in the same Elegy of Nyx. Those gathered in separate elegies react against one another, causing violent reactions when drawn upon for the wish. Whilst the wish sometimes does still work, the repercussions are great. Lives are the least of the prices paid.
More creatively, however, some have begun to understand the latent power and potency inherent to Hope's own tears. When stored and combined in enough strength, when mixed in grand vats of countless litres of Elpis's ichor, the material begins to react and change in strange, unpredictable ways.
They must be combined in careful ways by those skilled in understanding ichor's properties, else risk a catastrophic incident as mentioned above, but if the stars align, the resultant fuel is reportedly incredible for any purpose requiring stored magical energy. Those few who are this skilled keep their information close, though, so little is known of the processes - or who practices them.

Properties

Material Characteristics

Mortals bleed in their own colours, but the sky - the sky bleeds in all shades.

Whilst many-coloured liquids are not unique to things like ichor - chanceberry dye can be refined into similar iridescent rainbow shades - ichor is unique in its holographic, metallic nature. It often settles down into single colours when bottled, but when shaken, the colours of a full rainbow erupt with vibrancy and life. Shaking it is still not generally advised as it could cause a reaction to the magic internal to the bottled ichor.
Ichor generally manifests as this rainbow liquid, but on rare occasions, the elegies that spawn it can instead erupt with fury and cast down explosive crystals of the stuff. These crystals are the most dangerous and unstable form of ichor, and tend to adopt darker jewel tones - or even shades of black - instead of the glittering rainbow most ichor usually is.
These scarlet crystals, also known as dirge crystals, are hard like gemstones, but anything more than the slightest pressure causes their unstable magic to deteriorate in a massive explosion. Even those that seek to harvest ichor usually stay away from these natural crystals.

Crystallised Ichor by Hanhula (via Midjourney)

Experimentation has been underway in creating new forms of more stable ichor. Heating it into a gas results in a deadly shimmer in the sky that serves as an extremely dangerous source of radioactive energies and magical corruption; thankfully, it returns itself to the far less dangerous form of liquid ichor after some hours.
Freezing it or otherwise casting it into crystalline form has met with more success, and this is the form in which the most potent power crystals may be created. Though the crystalline form seems shelf-stable and able to withstand a greater amount of force than the darker ichor spawned by crimson elegies, it should be noted that a significant amount of damage to them will result in just as potent an explosion.

In Spellcasting

When used by mages, ichor of Elpis contributes intriguingly to the strength of most spells. Supposedly, this is because the concentration to cast a spell is similar enough to the making of a wish that ichor is compatible with spellcasting enough to be exceedingly useful.

Crimson Ichor by Hanhula (via Midjourney)

Despite being painfully rare and incredibly hard to get a hold of, spellcasters that are sufficiently supplied with ichor are worth the effort if sheer power is needed: a Fireball empowered and intensified by Hope's own blood is large enough to cleave a crater into what would have been a battlefield.
Though evidently knowledge of psychic magic is very limited, there are records in Impossibility dedicated to recent Shiari experimentation with ichor of Elpis harvested at the boundaries of the Starsear (prior to the dawning of Gaia's Lament).
Psychic casters, innately connected as they are to emotion and thought, seem to wield ichor in new ways entirely and gain access to entire new sets of spells and abilities through it. This does not seem to come without cost: the exposure drains their will and sanity, leaving them emotionless and murmuring in incoherent tongues. As the Lament spread shortly after these discoveries, it is not yet known if any way to reverse this damage - or even mitigate it - has yet been learnt.

Bottled Ichor of Elpis by Hanhula (via Midjourney)

Type

Elemental / Molecular

Odor

Petrichor and iron.

Taste

Like spiced honey with an aftertaste of burning.

Color

Iridescent, colour-shifting.

Common State

Liquid

Concerns on the Origin of Elpis's Ichor

Recent studies in Shiar have revealed disturbing effects on certain types of mage when exposed to the unbridled energies of the ichor of Elpis. Given the fears surrounding these discoveries, scholars of Celesthem Temple have begun looking into the reported effects to hopefully uncover some means of repairing the damage dealt.
Worryingly, the symptoms hold remarkable similarity to those reported to have been corrupted by outer deities - those that exist beyond understanding or comprehension, whose mere thought risks destabilising our world.
Is the ichor of Elpis a boon to humanity, or an insidious seed planted by an unknowable enemy? Official recommendation by High Priestess Aetha Tinuval is to cease experimentation at once until the nature of this ichor is better known.

Hope of an Elegy of Nyx by Hanhula (via Midjourney)