An animal Patronus has three main abilities:
Summon, Merge and Absorb.
Absorb is the standard ability to devour other souls to grow.
Summon is what Neville used just now, summoning the animal Patronus to fight for you, but his current Patronus is too weak to even take physical form, so it's useless now.
Finally, Merge fuses the shaman and the Patronus, completely sharing the Patronus' abilities, making the Shaman's form stronger.
The totems themselves also have passive functions, protecting the shaman's soul, mind and spirit.
This means that both their mind has some defense against Legilimens and they have protection against curses, and even death magic must pass through their Patronuses first.
Of course, receiving a killing curse now has a 99.99999...% chance of destroying his animal Patronus.
Summoning or merging with a patronus consumes spirituality, so it's not possible to remain merged indefinitely, unless the shaman can regenerate their spirituality faster than they lose it. While simply summoning a patronus in its spirit form costs very little, summoning the complete patronus or merging with it expends much more energy.
The upside of summoning the incomplete form is that the patronus is invisible to most normal people, except for those with high spirituality, such as wizards, who can see them in their incorporeal form.
The information he received also suggests that it's possible to permanently merge with the Patronus upon reaching the tenth ring, but there's no direct proof of this because there hasn't been a ten-ring shaman in a long time.
Neville didn't receive the shamans' legacy of knowledge, but he did receive their primary power, so he's very pleased.
Unfortunately, whether it's his current magic or the strength of his phoenix, nothing has truly allowed him to enjoy merging or summoning.
The strength of shamans is based on the number of rings and their completeness. Each ring is multiplied by twice the multiplication of the previous ring, starting with 1.
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Thus:
1 ring x 1 = 1
2 rings x 2 = 4
3 rings x 4 = 12
4 rings x 8 = 32
...
10 rings x 512 = 5120
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This means that if, for example, he can cast a 1-ring fireball spell that can burn a tree to ash, by the time he reaches ten rings, he can burn 5,120 trees with the same spell.
In general terms, it's like comparing Sasuke's initial fireball to Madara's great fire annihilation.
So it's no surprise that a ten-ring shaman could single handedly destroy a country, even if he only threw "fireballs" around.
So, with only two months left before Hogwarts started, he needed to improve the phoenix's strength, which currently wasn't even up to the standard of a one-ring.
Neville looked at the burn marks and ash on the floor and fell into deep thought, wondering how to explain this to his grandmother.
--x--
Neville convinced his grandmother to go to Diagon Alley the next day, the serious woman couldn't stand his puppy dog eyes.
In the end, even though she was tired from the whole event surrounding his fall from the second floor, courtesy of his great uncle Algie, she was exhausted.
In addition to her exasperation with Neville accidentally setting the phoenix egg on fire with magic, she had been feeling particularly tired for a week.
That's why the job of carrying Neville was delegated to him.
But when he saw the man arriving to accompany him, Neville wasn't so happy.
Neville wanted to ask his grandmother if she remembered that it had been a little over a week since Algie had thrown him from the second floor, but thinking she might change her mind, he just sighed and accepted the burden.
But the real reason for his unhappiness was that the man was carrying something on a cloth when he arrived.
His elderly face, with its gray mustache, was pulled up in a smile.
His bald head gleamed in the sunlight streaming through the windows, the sallow smile didn't cheer Neville up one bit.
He swore that if there was a frog in that cage, he would learn the transfiguration spell to turn his uncle into a frog in the future, so he could keep "Trevor" company.
-Neville, look what I brought you. - Algie seemed unaware of Neville's panicked eyes, instead, he walked past him and placed the cage on the polished wooden table, much to the dismay of his grandmother, who had no better face than Neville's.
The grandmother and grandson duo exchanged glances, finally, Augusta pushed Neville forward, making the boy swallow a sigh.
The man turned to him as Neville reluctantly walked on.
-Come on, open it, you'll like it! - The man smiled, quite pleased with himself.
Neville took a deep breath and placed his hand on the black cloth before slowly pulling the cloth away, asking for anything but a frog.
But when the duo saw what the elderly man had brought, they were both shocked.
A black raven was looking sideways at them.
Neville didn't know what to say for a moment as Augusta's lips trembled.
-A raven, Algie, really? - Augusta asked with a tired sigh.
-Yeah? Look how pretty it is, I had a lot of trouble getting it. - Algie nodded, pleased with himself.
Neville nearby didn't really believe ravens were bad luck, but giving someone a raven still seemed a bit... Bad omen?
Don't get him wrong, it's a pretty raven, but it's still a fucking raven!
Why can't you be a normal old man and get him a cat or an owl?!
Resigned, he saw the bright side. Ravens in the wizarding world are just as good as owls, but the reason they became unpopular was because they couldn't fly such long distances at once. Besides being noisy.
Aside from the distasteful meaning, the wizarding world is quite superstitious in some ways.
-Algie, Merlin! Who gives someone a raven as a gift? - Augusta tried to make the man see the point.
-Nonsense, they're just superstitions. Besides, look at this. - The man took out his wand and waved it at the raven.
The raven's mouth, which had been closed until then, finally opened. It flapped its beak a little, glaring angrily at Algie before turning to Neville.
-Sigh... Look, the new master is just a brat. The old mistress is so cruel. I only told the truth about her thick eyebrows preventing her from finding a husband, but she thanked me? No, she sold poor Klaus, she only charged him two galleons, I don't know whether to complain about being sold or how much I was sold for, what a cruel world, I should have been stuffed, at least I wouldn't have to go through abandonment, there should be a union for the crows, maybe I can be the president and... - The crow continued to chatter in his hoarse voice.
Beside him, Algie looked a little embarrassed, Augusta's lips trembled, and Neville...
Neville wanted to ask. - "Lagi, is that you?"[1]
As the bird continued to chatter, Neville and Augusta slowly turned to Algie, who looked away and pretended not to see.
Klaus, on the other hand, didn't stop talking, his train of thought constantly changing, but always in a negative, monotonous tone.
-...I really don't like that old potbellied thing. He always gave me rats, wild rats still. Oh, how can I eat those parasitic worms? It was a good thing he sold me to that little girl. It's a shame her mother didn't like it when I helped her make potions. Clearly, the more the merrier, right? She used crow saliva after all. I'm a crow, right? A spit or two more wouldn't hurt, it certainly wasn't my fault that it exploded!...
Augusta placed her hand over her forehead, trembling, trying to control herself from hitting her brother.
Neville was engrossed in the bird's life story, sometimes agreeing, sometimes mocking.
Even Algie couldn't stand it anymore, he waved his wand, finally silencing the bird.
The grandmother and grandson duo, as well as the raven, looked at the old man with strange eyes.
Algie coughed and said with a hard smile. - He's just joking.
-Algie... - Augusta's voice became dangerous, and the old man sighed.
-I didn't know he was like that. The woman sealed his mouth before selling him. It was only after I bought him that I found out. Anyway, it's a talking raven. You know how rare and smart they are. It only cost two galleons! It was a bargain! - Algie argued.
Augusta let out a long, tired sigh and looked at Neville, seeing what the boy thought.
Neville looked at the raven with some interest. Normal ravens can mimic the sound, achieving some ability of speech. In reality, talking ravens can not only speak normally, but are also very intelligent and witty. It's no wonder Ravenclaw, the Hogwarts house, has the raven as its symbol.
Besides, after his initial surprise, he found the raven quite interesting.
Neville saw his grandmother's look and nodded. - Well, it's better than a frog.
The raven next to him seemed to hang its head in defeat. Neville became curious and asked his uncle to remove the spell that prevented it from speaking.
-To think that being better than a frog is a form of praise... Sigh, the little master is truly thoughtful. I hope this is on my tombstone when I die, 'He was a better crow than a frog...', Yes, perhaps you'd prefer to stuff me. In that case, I could have a small pedestal with that inscription. Put a frog next to it, too, with the caption, 'Klaus was better than me.' Yes, that will make me look a little better...
Neville chuckled lightly, finding the raven very interesting and amusing.
-Your name is Klaus, right? - Neville interrupted the raven.
-...I see the little master has good ears. At least I won't have to explain the obvious to you if you explain it yourself... - Klaus continued in a monotone.
Neville rolled his eyes and was tempted to change his name to Lagi, but decided against it, letting the raven continue in his quirk.
-The letter says I can only bring one owl, one cat, or one frog. Will that be a problem? - Neville asked his grandmother.
-Oh, don't worry about that, it's more of a suggestion. Some other domestic animals, like rats, dogs, and... crows, are also allowed. - Augusta sighed and explained reluctantly.
-Okay. - Neville nodded, walked over, and opened the cage.
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[1] - Character from The Legendary Mechanic.
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I'm thinking about the horror movies I'll use. If you want to help me, you can join the discord I created for this purpose.
discord.gg/jHKCXjGjFx
I'll leave the code in the comments.