The strategy to this deck is to find the 3-card combo: Black Garden, Malefic Rainbow Dragon, and Dragon's Bind, Ideally with a 4th card Field Barrier. Black Garden halves Malefic Rainbow Dragon's attack to 2000, making it eligible to use with Dragon's Bind, which specifies the original attack of the Dragon monster, so your opponent will be unable to special summon any monster with under 4k ATK. Speedroid Terrortop, Deep Sea Diva, and Draconnect, which is searchable with Cynet Mining, are all 1-card level 5 Synchros, use them to make Garden Rose Maiden and search Black Garden to your hand. Malefic Rainbow Dragon is played at 3 and is also searchable by The Melody of Awakening Dragon, which will get you 2, you can get rid of the one that is dead in your hand with Allure of Darkness. Dragon's Bind and Field Barrier are unsearchable 3-ofs, so you need to use 3 Pot of Prosperity to help you find them. The side deck is filled with cards that be used by other build options for this deck.
One weakness of the deck is that it has no follow-up play even in the (somewhat unlikely) event it goes off. Since Black Garden can be reliably searched by a level 5 synchro, at the cost of only a tiny amount of consistency, 1x Terraforming, 2x Black Garden, and 1x Cynet mining can be removed for 1x Malefic Truth Dragon, 1x Foolish Burial and 1x Dragon Shrine to put it in the GY, and 1 more copy of Allure of Darkness in case it ends up in your hand. Malefic Truth Dragon provides some recovery if they manage to get rid of Malefic Rainbow Dragon.
Another weakness is how bad the deck is going second. By again removing 1x Terraforming, 2x Black Garden, 1x Cynet Mining, and 1x Upstart Goblin, and adding 1x Neos, 3x Neos Fusion, and an additional Rainbow Dragon, (or keep upstart) you can have Rainbow Neos' powerful board wipes for going second. Alternatively, you could remove those same 5 cards for hand traps such as Ash Blossom and InfImp.
The last card in the side deck is Imperial Custom, which protects continuous traps. If you play this card, it is possible to add it as 5th card to enhance the lockdown.
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