Flying, first strike, trample, lifelink, and haste for just give mana on any Spider you play is potentially game-winning, especially now the Spider-Man set has printed so many new tools for the creature type
You might also want to include as many orcs and goblins as you can for sacrifice fodder
Both halves matter against a deck like Dimir, but the fact that one half will matter against most decks means this is likely maindeckable
Lightening Helix 3.0 Power 3.6 Support 2.4 The helix is vastly overrated by most players in most formats
Simply flash a bunch of creatures in prior to your turn, play spells as necessary, hit an opponent with your creatures, untap your lands, and you essentially have free mana to do the same thing again