Hi there, thank you for putting effort into this.
A bit feedback from my part. Don't take this as too over critical, I think this is a very good tutorial and I just want to provide some input to make it more newbie accessible.
You can leave the flavor text as is, but i would heavily suggest to add another paragraph afterwards, something like this:
"Over three ages you will draft cards and battle your opponents, while the game board gets smaller and smaller due to the unfolding end of the world."
Also i would give people some early indication about game victory, as everyone looks for such a clue as early as possible. Something like:
The player that has the most glory at the end of the game wins. Glory will be gathered by several means, like winning battles, fulfilling quests, drafting special upgrades or maxing out your clan stats. We will look at those things throughout this tutorial."
When explaining the clan stats section, give a little teaser about the three stats:
Rage limits the amount of things you can do during an age
Axes provide additional glory for won battles
Horns increase the limit of units you can have on the game board.
We will look at those in detail when we go through the age.
Description of regions:
When mentioning Villages, i would immediately explain that these limit the units that can be placed in a region and that there is no unit limit in Yig.
Its good to mention it later on again when you explain invade, but I would already tease it as soon as you mention the word "village".
Starting out with play upgrade is a little bit unfortunate since the opponents already started with "invade" and basically invade is also a part of the rules when entering with the troll.
So I think a perfect way for this would have been to start the action tutorial with "perfom invade" and explain it. I understand that you have put insane effort into this and think that the majority of the tutorial is perfect, so of course this is no reason to redo the tutotial.
So to fix this i would reorganize the text after the "you are doing great so far..." part:
Your opponents have all taken their first action and performed 'invade' with a warrior. Invade lets you put new units on the board and it will be addressed soon"...
This is similar to your strcuture, but I think the newbie should understand why all of a sudden 3 enemy warriors are on the board
Also, as the troll is the first invade that you perform, i think this is the place to explain horns in detail. But this is just a personal preference, since
the explanation you do later on in the Yggdrasil section is very good.
Point out that even though the leader has 3STR, you just invaded for free because of the special text.
This is IMHO very close to perfect and comprehensive. As said earlier, I think starting out with upgrade/troll is a bit clunky as you begin with the most complex action. But that is rather nitpicky from my part