The counter effect is reliable against a lot of different spells and costs only one mana
Each of those includes 100 cards made up of both reprints of existing cards with new Final Fantasy art and brand new cards designed with Magics most popular format, Commander, in mind
Not only does it turn all your lands into Deserts, making up for the limited options available in the land type, but it also lets you mill cards, enabling many of the lands in graveyard synergies the deck offers
I wrote about her in my Archetypes You Can Build in an Hour article, but suffice to say, you can get a really consistent build going just by using her ability
Although both of these effects are useful, theres no real synergy between them, beyond the fact that they are both vaguely Control focussed effects