See Storm Prophet. A second attempt at Ascended, this time conceptualized for Urmak (bad Soviet times continent).

How many 2/2 red Avatars with haste and trample would be in the set?

It is my opinion that - for purposes like your ascend - we should take the keyword action "conjure" from digital to paper and add rulings that specify you can only conjure from your sideboard. As long as you conjure in a way where the made public information in your design (like here) there is no need to restrict it to digital.

That would mean you could go back to naming the cards or using a marker type.

I realize I ran into the problem that the Avatar was designed as a token, but wants to become a real creature card once it enters the battlefield, however it isn't intended to be playable if not ascended. That would require either making an ability that says the creature could not be played unless it was added from the sideboard during a game (even more problems, since what happens if it got shuffled into the deck, how does an opponent know whether or not the player had a copy that was in the main deck sitting in their hand, etc.), or making the Avatar at an impractical cost, where normal casting would be an undesirable choice. This is more challenging than I anticipated.

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I don't think the trouble of working conjure from digital to paper is worth the effort over just using abilities similar to cards that make use of cards in the sideboard. If the environment and setting were right, then I could see something like a checklist card, or maybe the blank cards like Kamigawa: Neon Dynasty had.

> "That would require either making an ability that says the creature could not be played unless it was added from the sideboard during a game (even more problems, since what happens if it got shuffled into the deck, how does an opponent know whether or not the player had a copy that was in the main deck sitting in their hand, etc.)"

You already have "Biting Gale Ascended can't start the game in your deck." on one of them, so you are open to some text. I think the key is not going for explicit rules text, but outright creating a new card type/supertype or a keyword ability that is covered in the rules.

Do you recall hero cards from the Hero's Path Challenge Decks? You could just have a type or keyword like the infamous "forbidden" spells.

Or you just keep the cards at a prohibitive/suboptimal cost, so people can play them if they want to, but they're only really good played through ascension.

The text on Biting Gale Ascended was something I thought of last night, after I had made that statement.

I think a drawback on the prohibitive cost requires multiple cards for a single card, meaning the card cannot do anything if the player doesn't have the accompanying card. I did not consider that problem before. Transform is also undesirable, since multiple creatures would likely have access to the same ascended form, unless precedent could be set to have multiple cards have the same card identity on their transformed side. Double-sided would also lead to the limitation that both sides should have the same toughness, which could be a problem.

From your Hero's Path suggestion, Ascended as a card type in the token slot with the rider text of Biting Gale Ascended would be the next option. This would lead each creature that can ascend to have the reminder text on the card, which would eat up a lot of text space.