In reality, while it certainly introduced some new toys for the format, a lot of people associate the set more with the likes of the banned Hogaak, Arisen Necropolis, the obnoxiously expensive Force of Negation, and some really cool Commander cards
Oblivion Ring on Lorwyn wasn't enough, and little by little, other cards were released in later sets to effectively tame Planeswalkers outside combat, culminating in Hero's Downfall on Theros
Their opponents can also play instant spells and abilities as before, too
Here's a list of "commons" that a friend and I found in their bins: I found duplicates of most of these cards and quickly had play sets of some very nice, old cards
In Mark's article "Game On," he goes more into how we approach this in our Universes Beyond sets
A creature that can produce more mana, like Incubation Druid , will also produce infinite mana at the same time