Yes. Advanced Ritual Art can substitute in for almost any ritual card. For example, it can summon Divine Grace - Northwemko, despite that saying it can only be summoned by Ritual of Grace.
Advanced Ritual Art can therefore summon Evigishki Gustrake, you don't necessarily have to use one of the three Gishki ritual spells.
No, it is a mandatory trigger and cannot miss the timing.
Yes, Advanced Ritual Art can be used to summon any Ritual Monster from your hand or Deck, as long as you meet the specific requirements for that monster's Ritual Summon. The card allows you to send monsters from your hand or field to the Graveyard as the required Tribute, which can help you fulfill the Level requirement of the Ritual Monster. However, you must still adhere to the specific summoning conditions outlined by the Ritual Monster's card.
Not all, but most. If you look at some Ritual Monsters, they say they can 'only' be special summoned by a specific card, others do not. So you are free to summon a Relinquished using either Black Illusion Ritual, or Contract with the Abyss, or Advanced Ritual Art, but you could not use any other card other than "Ritual of Grace" to summon "Divine Grace - Northwemko".
Yes, it does have to be in your hand.
All Ritual Summons are considered a Special Summon. However, not all Special Summons are considered a Ritual Summon. A Ritual Summon can only be performed with a Ritual Spell Card and a Ritual Monster. A Special Summon refers to any monster that is placed on the field in a way that is not a Normal Summon, Flip Summon, or Set. Also, Ritual Summons are never considered a Normal Summon.
No, because it wasn't 'properly' special summoned. To be able to special summon a Ritual Monster from the graveyard, it has to be initially summoned by Ritual Summon. Ritual Foregone does not Ritual Summon.
A Ritual Summon is a kind of Special Summon. Anything that affects a Special Summon (such as "Bottomless Trap Hole", "Royal Oppression", etc.) will affect a Ritual Summon.
only if the monster has been summoned to the field, and the summon was not negated. also, if the card says 'this can only be -insert summon type- summoned by -insert ritual/Special summon info- ritual summon only (this card can only be ritual summoned by) -Only ritual summon Special summon only(This card can only be Special summoned by) -Only special summon, hope this helps.
Obelisk the Tormentor (Effect Monster) is not Ritual Summoned nor does it require a ritual. To summon Obelisk the Tormentor, you must Tribute 3 monsters (it is treated as a Tribute Summon).
No, Ritual Monsters are 'special summon only' monsters, the only way they can initially reach the field is by Ritual Summon through an appropriate spell card, or by a card that specifically allows you to ignore this, like Ritual Foregone.
Only if the card specifically says it can summon a Ritual Monster, like Ritual Foregone. Otherwise, you can't do it, cards like A Hero Emerges, or Monster Gate, cannot special summon a Ritual Monster.Also if you summon the Ritual Monster properly, by Ritual Summon, and it is then sent to the graveyard for whatever reason, then you may bring it back to the field using cards like Monster Reborn. However you cannot simply discard a Ritual Monster from hand and try using Monster Reborn straight away, they are a form of special summon only monster, simply by being Ritual Monsters.
Nothing stops you putting a specific Ritual Monster in your deck, without its Ritual Spell Card. You are free to take monsters who you are unable to summon. It might be that you plan to summon the Ritual Monster with a card like Ritual Foregone. Or it could be the component in a Fusion, for which you never intend to actually summon the component itself.