This deck isn't the most optimal build but it's the one I personally use. If you go first the main combo is trying to make Winda and Dragostapelia/Mirrorjade using the least cards possible (mainly because in this build there's only one copy of Shaddol Beast, Aluber and Branded Opening).
The 3 fusions on the side deck are useful if you want to switch some staples from the side to the main removing the Invoked Engine because you free up to 4 spaces in the Extra Deck. The rest of the side deck is basically some random stuff I putted there; if you want a more useful side then I think the best cards are 3 Lancea and some backrow removal, since the deck is very weak to Flowandereeze and stun builds.
Some useful cards you can add in the main are a Predaplant engine (with also Fusion Destiny and DPE, but that would take it further from budget range), another 2 Aluber's copies, Ad libitum and Quaeritis, Dogmatika Maximus, Super Polymerization and every staple you want.
Feel free to gave advice in the comments and remember that this is a budget list of a deck i own in irl, so a lot of choices are determined by that.
240
330
420
660
