Yan Lin was already a Retired Badass canonically, but she gets to take more part in action in this fic. For example, she knows the Vulcan neck pinch and basic chi stun-spells.
In her return thanks to Tarakudo, the Queen can summon the Ninja Khan and the Razor Khan. It's theorized that it's because the Razor Khan mask had been worn for the first time in centuries.
Jade being cured of her second stint as the Queen by Will using the Heart creates a sixth Auremere bound to her, turning her into a Guardian with shadow powers.
When Hak Foo first appeared as a Dark Chi Warrior, he had a Super-Toughness that allowed him to survive being crushed under a boulder and was defeated only when Uncle used the strength provided by the Ox Talisman to throw him down a cliff. In this version of said instance, he's even more durable; when Will uses her enhanced Guardian strength to bombard him with punches and kicks, she gets sore fists for the effort. The Guardians need to resort to trapping him in a vortex of their elemental magic and a blast from the Dragon Talisman, and the resulting explosion that sends him flying first up and then down is what finally vaporizes him.
Unlike in canon, Paco actually fights by using wrestling moves he has learned from El Toro when he returns in the latter half of the story (though he's also using the Ox Talisman to even the odds).
In the Christmas Episode, Saint Nicholas and his elves are considerably more powerful and skilled than Santa was in JCA canon. While the canon Santa was mostly helpless, Nicholas puts up an impressive fight against Wong and Cedric, forcing them to summon Hak Foo to gain enough of an edge to allow them to restrain him, which says a lot about Nicholas given Hak Foo's previously mentioned feats, and even after Wong steals his magic he still joins the fight against Krampus, matching the demon with pure muscle.
In addition to his demonic abilities and the Talisman powers, Shendu uses Tarakudo's mask to take control of all the Shadowkhan tribes once Wong resurrects him. In canon, he only ever controlled the ninja tribe.
Hak Foo is the one to get Drago's dragon speed, Frost gets dragon strength, and Raythor gets dragon flame, with the power even restoring his lost muscles.
Drago has his mother's Quintessence powers (if to a lesser degree than her) in addition to his natural fire demon abilities.
In general Quintessence magic is more powerful in this story, to better reflect its supposed power that was never fully explored in canon. For example, one of Will's lessons has her learn to manipulate the life-force in plants, and she later learns how to communicate with animals through their life-force.
Since Drago uses his Quintessence powers to bring the Annihilators to life in this take on things, they have claws and are linked to him, allowing him to direct them to do more than just mindlessly rampage towards the palace.
Canonically, the Ben-Shui monks were by all appearances non-combatants. Here, they're all Warrior Monks able to hold their own against Drago in a fight, with the High Mystic in particular actually winning against him before being sneak attacked from behind by Nerissa.
