You can untap it by putting a -1/-1 counter on it, so pair it with something that offsets the counters or turns it into a non-creature, and youve got infinite green mana
If "OP13-064 Gol.D.Roger" stays on the field, you no longer need to worry about giving your Leader DON
Finally, Spider-Man's powers are based on an animal, and the comics have shown that there is a certain destiny to his connection to both spiders and the Spider-Man universe, which is all core green. "We're not limiting ourselves to any one [comic] run or series." In addition to the Scene Box, the set will have the usual Play Boosters, Collector Boosters, Bundles, and Prerelease Packs, all of which can also be seen in the gallery above with more details
You can play Recruiter, stack your deck and then make sure every Ringleader draws you three goblins plus another Ringleader to do it again
Here's how
you cant play more than two colors if you want to leverage these and even thats pushing the bar