To explain the combo:
Utopia Sprawl, Fertile Ground, and Harvest Festival all go on a single forest (Yes we scoop against land destruction). Psychic puppetry is continually spliced on to cheap arcane spells, making mana and drawing through your deck. Eventually you have a land that makes 7 mana, and that with Psychic puppetry and Petals of insight makes infinite mana and draws you to three cards in a row, with you then kill with Stream of thought replicated enough to kill.
There is neat trick that allows an easier setup:
A land that tapped for 6 mana, along with Petals and Puppetry in hand, if the remaining cards in the deck is not divisible by 3, is a deterministic kill. Continually casting Petals of Insight, netting no additional mana, allows for one to manipulate the cards being put on the bottom of the deck, eventually reordering the entire deck, and drawing whatever 3 cards are needed.
The 3 cards to get in any normal circumstance: any cheap arcane spell, any 1 or 2 cost enchantment, and the other Petals of Insight. The arcane spell with the Pupperty in hand generates floating mana, the enchantment is played with the mana onto the mega-land to bringing it up to the 7 mana threshold, and the second Petals of Insight is looped to make infinite mana and find Stream of Thought and kill.
A explanation of how splice works is provided in the comments.