All the series members shares elements in their designs like bodies made of cristals encased in a robotic-looking armor, while following a greco-roman mythology name/design pattern for some of their members.
Something to be noted is how they seem to be divided in two art styles despite having the aforementioned elements and being part of the same series - some of the series members seems to posses a more human appearance (looking at their body structure, like hands and faces) like Meltiel, Sage of the Sky. While others have a more mechanical design, having disjointed arms/hands, a face adorned with lines and a single metallic dot (that could serve has the monster's eye), also they reveal less of their crystalline bodies, making them look a lot like the Majestic Mech series (specially Majestic Mech - Senku) like Bountiful Artemis.
On their own, the Counter Fairies do not synergize well, but work to support other Fairy archetypes. Their support effects trigger when a Counter Trap successfully activates and/or resolves, and either destroy cards on the field or replenish the player's hand, maintaining card advantage. Counter Traps like "Magic Jammer," "Seven Tools of the Bandit," and "Drastic Drop Off" are best, as the effects of the Counter Fairies will make up for the lost resources used to activate those cards. "Malfunction" and "Goblin Out of the Frying Pan" are also useful; while they do not directly destroy cards, the opponent will have to activate their card again, triggering the effects of the Counter Fairies twice. The "Solemn" series is also useful.
With cards like "Banisher of the Light" and "Banisher of the Radiance", the player can form a loop using "Layard the Liberator". When using a Counter Trap that has a discard cost, like "Magic Jammer," "Divine Wrath," or "Destruction Jammer," the player can discard a Fairy-type monster for the activation cost, then use the effect of "Layard" to return that Fairy to the hand along with another discarded Fairy. The banishment effects of "Banisher of the Light" and "Banisher of the Radiance" will further deprive the opponent of resources as their destroyed and negated cards are banished, while "Layard" keeps returning the player's banished Fairies to the hand for use.
With the introduction of "Guiding Ariadne", Counter Fairies have gained the ability to use any Counter Trap for no cost, due to "Ariadne's" Pendulum Effect. Because of this, even if the player's LP or hand are low, they can still use cards such as "Cursed Seal of the Forbidden Spell" or the "Solemn" traps without putting themselves at more of a disadvantage.
Banisher of the Radiance, Royal Knight ´(along with the aforementioned Majestic Mech series and to some extend the Parshath archetype) and Nova Summoner shares the same design style of the counter fairies despite not being related to them effect wise.