2nd time participating this event, so here's my take of Circular for Vendreads, my all time favorite archetype.
Obviously this does more than be a Circular for the deck, it's both a starter and an extender that attempts to fix a majority of the deck's issue.
Sending it from deck to GY with for example Foolish Burial/Zombie Vampire or using Ravenous Vendread/Revendread Evolution to Ritual Battlelord will let you add this back to your hand, then foolish a Vendread monster
Then with it's in hand effect, you Circular for any of the Ritual monsters or Scar of the Vendread to search a Vendread Spell/Trap, typically your Ritual Spells
Then you get to summon any Zombie from GY or banishment plus itself, most of the time you would summon the Vendread monster you sent via the first eff to do Ritual plays, but if you have extended quite a bit, you can summon your banished Vendreads or other Zombies and pop off
Source art is from here
https://yu-gi-oh.jp/news_detail.php?page=details&id=2392