This control deck aims to either rush into Lancea for Raiho/warlock interruptions or set up a Kosmoclor/curse lock on your opponent. If you get to go first, then swap in barrier statues and dimensional barriers for additional pressure on the opponent. Defender is useful against Tenpai and other go second strategies, other cards in the side are for use cases with Crossout or when you're forced to go second.
If you're looking for more ways to make synchro 10's, deep sea diva with guitar is a one card combo that I opted not to use in favor of normalling Aegerine. Guitar can also banish itself to trigger Chengying which can be useful for the grind game.
If you have little knight, go ahead and use her. Personally, I can't afford to blow that much money on a single card (she literally would double the deck's cost).