This deck performed leagues better than I ever expected it to, since it started as a build I found on YGOPro myself and modified into the powerhouse it is now
(Shoutout to the original legend here) - https://ygoprodeck.com/a-budget-way-for-a-melffy-day/
MONSTERS
For the meat of the deck, Melffys, the three best for this build are Fennec, Puppy, and Catty. By returning to your hand on an opponent's summon or battle declaration, Fennec allows you to special summon a Beast from the hand, Puppy allows you to special summon a Level 2 Beast from the deck, and Catty allows you to add a Beast to your hand from the deck. Overall, these three have the best main-deck synergy and open up the board to the other combos of the deck. Ponpoko is a great lead into Tantan, who can special summon Kalantosa, which when special summoned by a Beast, it can destroy any card on the field. This makes Kalantosa the main-deck's carry to maintain board. Additionally, Valerifawn has the ability to special summon Kalantosa from the GY (proccing effect), and leading into, at lowest, level 4 synchro plays. Alpha is also a good emergency monster for when the opponent has board, between being able to special summon from hand if your opponent has a higher total attack point value (which is common since Melffys have the attacking power of a wet napkin), and being able to send Beasts from the field back to the hand to send face-up monsters on your opponent's field to their hand (which is good for clearing extra deck summons). To top it off, Barrier Statue of the Drought is a safety net to keep your opponent from building a non-Earth board for as long as possible.
SPELLS
Most importantly, Obedience Schooled is ideal in a starting hand, first or second. Special summons three Level 2 or lower Beasts from the deck to the field, with the drawback of their effects being negated and only being able to summon Beasts for the rest of the turn (which is good for this deck, since extra deck plays are the build's extenders and carry). Equally important, Hide-and-Seek, which prevents card effect destruction once per turn and can shuffle three Beasts with different names from the GY to the deck, then drawing one card afterwards. Next, Child's Play is incredible in a combo-heavy meta and, if your opponent goes nuts, 10,000 life points is easy to achieve to prevent your monsters from being destroyed by battle, and Foolish Burial is included for the sake of getting Kalantosa to the GY easily to pave the way for Valerifawn. For control, Twin Twisters and Harpie's Feather Duster are solid means of keeping backrow in check.
TRAPS
Mirror Force. Less is more.
EXTRA DECK
Melffy Mommy and Melffy of the Forest are essential to keep this deck well-oiled. Ideally, with starting hand including Obedience Schooled, going OS into Melffy of the Forest is the go-to first play. Then, if Hide-and-Seek isn't in the starting hand, using Forest's effect to get it is the next move. Play H&S, and if there's another Level 2 monster in your starting hand, you could always use it and the other monster summoned by OS to start Mommy, who at 5 materials becomes the ultimate attacker for the deck. Mommy has three stages; at 3 materials, she cannot be destroyed by battle. At 4, you take no battle damage from battles involving her. at 5, any attack position monster she's included in a battle against (whether she's in attack or defense position), her effect deals damage to your opponent equal to the opponent's monster's attack. This is the deck's boss monster and win condition, if successfully protected by H&S and Mirror Force.
Secondarily, Number 64 is good for challenging heavy boards due to its ability to summon tokens with attack equal to the highest attack on the field, and Marjoram alongside Child's Play is a good way to clear cards on the field (once per turn) if Kalantosa isn't an option. Dark Mist is included for grins, but can come in handy in tight spots, as well as the other synchro monsters included in this build.
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