Beast Quest

Written by Adam Blade (a representation of multiple authors), Beast Quest is the story of two 10-year-olds, Tom and Elenna, as well as Storm and Silver (his horse and her wolf, respectively) fighting several Beasts, for whatever reason (usually to uncover artifacts the the Big Bad has hidden, or because said Beasts are Brainwashed and Crazy). The adventures usually take place in the fictional Avantia, but do go elsewhere at times.

The cast is quite small, and while the authors clearly do not read back over their books, the series can be fairly entertaining.

Spawned a spinoff, The Chronicles Of Avantia.

Tropes used in Beast Quest include:

All There in the Manual: The "Novelty" books provide a lot of backstory for the main books, such as Storm waiting for a Chosen One, and details of Elenna's childhood.
The Archer
Badass: YMMV, but given that Tom IS only a 10 year old (of course, he is also kind of a Mary Sue).
Big Bad Ensemble: We've had a few villains other than Malvel.
Bottomless Magazines: Surprisingly averted! Elenna is shown making new arrows on a few occasions, and she does run out sometimes. Luckily her last shots are the only ones that actually do damage.
Brainwashed and Crazy: The premise for Series 1 is that Avantia's beasts have become Brainwashed And Crazy, due to meddling of the Big Bad, Malvel.
Catch Phrase: "While there's blood in my veins..."
- Tom actually gets called out on it several times, later on.
Child Soldier: Tom is knighted at the end of the first series by King Hugo.
- Turns out that Hugo already had a battalion of child soldiers, including Tom's Disappeared Dad.
Chosen One: Tom
Chronic Hero Syndrome: Also Tom.
Cold Sniper: Elenna becomes this when she's corrupted by the Arena, in "Mortaxe".
Disappeared Dad: Tom's father. He shows up in Series 4, Only Mostly Dead.
Everything's Better with Indexes: It would be easier to use this as opposed to a separate trope for every single creature that shows up in the books.
Half the Man He Used To Be: A few times, but the best example would be Tom's mother cutting Velmal in half with Tom's sword.
Handicapped Badass: Tom gets his right hand covered in venom in Series 6, crippling him until he's cured.
Harsher in Hindsight: Tom and Elenna are both orphans raised by their aunts & uncles, and even then, Elenna states that hers wouldn't care if she left. Guess who gets their parents back.
Heroes Prefer Swords
Improvised Weapon: The prime example would be in "Carnivora", where Elenna fires shards of ice at the Beast when she breathes fire, in order to have the ice shatter and impale her body.
Infant Immortality: Played straight until series 8 or so, when Malvel kills Marc.
Luckily, My Shield Will Protect Me: Tom's trademark is a shield adorned with "tokens" from the six beasts of Avantia, giving him six different blessings/ abilities]].
Missing Mom: Tom's mother died in childbirth. She shows up in Series 6, Brainwashed and Crazy, but gets saved in Series 7.
Moral Event Horizon: Malvel arguably crosses this by turning Silver into The Wild Terror.
Parental Abandonment: What really happened to Tom, as opposed to what he believes happened.
No Ontological Inertia: Normally averted (by having victims just live with the damage done), but played straight with Hawkite's damage being reversed when he's restored. This includes a guy being brought back to life.
Save the Villain: Tom will never let a human die (except Malvel or any other Big Bad). Turns out to be beneficial in "Arax".
The Starscream: Petra to Malvel at the end of "Warlock's Staff".
Villain Decay: Until Tom showed up, Malvel was a force that probably gave King Hugo nightmares. Then he lost to a 10 year old kid. Repeatedly.
- Malvel makes a comeback during Series 10. Among other things he kills Tom's parents. For real this time.