Gydion

How does Mind Grip work with Gydion?

Apply raw (Gydion's silver).

1. Does Gydion start the game with all spells in his spellbook? 2. Does Snori start the game with his runes set?

Follow all card texts verbatim. If it's not in the text, then it's not a thing.

With Gydion's Raise the Dead, I respawned a minion in a different spot within the battle zone than where it started, since one had been moved from its spawn. Is that correct — you don't have to respawn a minion at its original spawn point? Also, can Raise the Dead ever give you more minions than you started with in a zone? If a minion was moved out of the zone but none were killed, can you revive one from the supply?

For your first question, you played correctly. if there was a restriction, it would be in the card text (For example, Dodger's green). For your second question, please check "Respawn" keyword on Page 19.

Does an "if able" always apply to the full sentence? For example, Gydion's Energy Drain: "An enemy hero in range discards a non-basic card, if able. Your team regains 1 spent life counter." Does that mean that I have to be able to target an enemy hero for the life counter to be regained or does the "if able" remove the "being able to target" part as well as discard part.

Direct answer to the first part of your question is in the rulebook. Page 17.

For Gydion's cards that scale with removed cards, do you choose how many cards to remove as you do the action (for example, can you remove all of your spell cards to get a bunch of coins), or does it only count the ones you have already played when you play the skill?

The spell cards are removed from the spellbook either when a spell is cast, or when a spell effect tell you you can do it. You cannot choose to remove them at will.

Does Gydion start with a spellbook, or does he only get it after he prepares the spellbook for the first time?

Unless the card specifically says that he does, he doesn't.

Can Gydion's spell cards be used to perform a clear action? I mean, do the red and gold spell cards count as a "complete attack action"?

Yes, for the same reason he can fast travel with Expeditious retreat

When Gydion gains his Ultimate, does it take 6 rounds before he can trigger the Wish spell win?

The answer is 5, not 6.

Is Gydion able to play a spell card if there is no target / it is invalid for use?

Same way as any other action. You stop performing an action at the exact spot when you cannot do a mandatory step.

With Gydion's Suggestion spell, does the opponent choose the direction they move?

Correct. Just note that they do not _start_ in the spellbook

Gydion's silver reads: "Only Gydion can look at the cards in the spellbook". Is this a hard counter to NebKher's gold ("Perform an action on the card in the previous turn slot for an enemy hero...")? If NebKher attempts to target one of Gydion's other cards (red, blue, etc.) that casts a spell from the spellbook, does this fail to find due to the text on Gydion's silver?

No. See Gydion's silver text. Spells are revealed when cast.

How does Gydion's Suggestion work? Who chooses the direction, and if it's the person being suggested, can they move in a direction that doesn't move them 3 spaces?

See Page 10 of the rulebook, "Performing actions".

If a Gydion player revealed a card that reads (for example) "cast Spell A, B, or C", and I act before him, am I allowed to look at spells A/B/C if they are still in his spellbook?

The answer is on Gydion's silver card.