What's different about the first run?

Question

What's different about the first run? Or is that too large a question?

I'm wondering what the best one would be, in terms of Meta Progression... It seems like Nectar and Gemstones don't appear as Chamber Rewards on the first run? Or is it just not rewards in Tartarus?

Or have I just been astoundingly unlucky, having my only source of just 1 Nectar be Dionysus?

If so, when or where do they start appearing? If Gemstones, perhaps Run 2, and maybe only on skull chambers, if my two data points are right enough.

...

Then there's Boons, with only Athena, Artemis, Ares, and Dionysus seeming to be available for the first run?

I assume there's further differences as well, given what I've read on the Wiki?

According to a YouTube guide by Pryde, first run Charon shops don't show any of those who haven't been spoken to.

And speaking of Chambers, Asphodel can have Food as a reward, if things go wrong / right.

Answer 1

I believe this to be a mostly complete tally of the differences of the first run in Hades but I may have missed a few things or gotten a few things wrong, corrections and additions are welcome.

The following quirks of the first run are inherent to the run itself:

• Only 4 of the gods will provide boons (Ares, Artemis, Athena, and Dionysius), the remaining gods (Aphrodite, Demeter, Hermes, Poseidon and Zeus) will not provide boons as room rewards nor in Charon's shops.

• The first boon is guaranteed to be from Athena and contain her attack, cast and dash

• No Wells of Charon in chambers (unlocked on run 2) (the ones after boss rooms are still there)

• No Daedelus Hammers (unlocked on run 3*)

• No Trial of the Gods (unlocked on run 4)

• No Chaos Gates (unlocked on run 5*)

• No Calls (unlocked on run 6)

• No NPC chambers (Sisyphus & Bouldy, Eurydice or Patroclus) (unlocked after beating their respective biome boss for the first time)

• Food may appear as a chamber reward (This is apparently to replace NPC chambers which cannot occur in the first run)

• The boss of Tartarus will be Megaera (the remaining Furies will begin to appear after beating Meg a certain number of times)

• No Thanatos (must first encounter either Alecto or Tisiphone)

• Charon cannot be robbed (unlocked after beating the final boss)

These quirks anecdotally seem to hold based on self-gathered data and a handful of fresh file speed run videos** but otherwise have no source:

• Gemstones (seems to unlock on run 2) and Nectar (seems to unlock on run 3) will never appear as chamber rewards or in shops, blue laurel chambers will only offer Darkness, Chthonic Keys and rarely food

• Survival rooms do not appear (seems to unlock on run 2)

These quirks of the first run are determined by virtue of not starting at the House of Hades and not having gained any artifact currency yet (Chthonic Keys, Darkness, Titan's Blood, etc.)

• Weapon must be the Stygian Blade (Zagreus aspect, no upgrades)

• No Mirror of Night bonuses (50 base HP, 1 dash, no death's defiance, etc.)

• No House Contractor upgrades (no Fountain Chambers, Infernal Troves, Infernal Gates, Fishing, etc.)

• No Keepsakes/Companions (none available by default and 'Keepsake Collection, Regional' that allows switching between biomes is a House Contractor upgrade)

• No Pact of Punishment (must beat final boss or begin game in Hell mode)

This last one is non-gameplay related but is somewhat of a spoiler:

Hades has different dialogue when you encounter him to account for the fact that his usual dialogue doesn't make sense on the first run

Footnotes

* Personal testing seems to contradict the linked sources, a Daedelus Hammer appears in run 3 not 4 and Chaos Gates first occur in run 5 not 7, maybe those pieces are obsolete due to updates to the game

** Testing consisted of 3 fresh files with 6 runs apiece and 6 fresh file speed run videos from Youtube done between Nov 2020 and Oct 2021