Its true that cards like Nissa and Questing Beast are usually good enough to win the game, but threats that close quickly, consistently and resiliently can tempt players into aiming a little higher
They still will need to rely on other colors for interacting with their opponents' board though
Mana Value 5 and Beyond More expensive green ramp cards can offer even more of a mana advantage, but these cards usually only see play in decks that are truly gluttonous for mana
Yes, it's definitely time to go digging through your old boxes to see if you've got a copy
Playing an extra land ramps you, and these decks usually have high land counts
It takes a while before a deck with the number of nonbasic lands tri-color decks would naturally play would get to stop sacrificing lands, and many of even your similarly colored opponents will be able to keep operating for a similar amount of time unless you bust this out right away