This deck is slightly competitive, but can lean towards the fun side.
The main goal is to XYZ Summon "Lyrilusc - Assembled Nightingale", able to directly attack your opponent and, by removing XYZ material, can keep itself on the Field without the player losing LP. It is important to swarm the Field with as many Level 1 monsters as possible for this reason. All of the Main Deck monsters that are not "Lyrilusc" contributes to swarming and/or protecting the player from battle/effect damage.
Highly recommended that "Assembled Nightingale" is XYZ Summoned only when "Lyrilusc - Cobalt Sparrow" is able to become XYZ material because of its effect that gives "Assembled Nightingale" immunity to becoming target of opponent card effects.
General ATK power is very low, so "Borreload Dragon" and "Borrelswoard Dragon" are in the Extra Deck in case of situations that require higher ATK.
"Psychic Blade" is used to boost "Assembled Nightingale"'s ATK to achieve OTK. "Instant Fusion" is used to Summon Fusion monsters if needed and also serves as a method to swarm.