They were different, they were beautiful, and they brought a lot of long-awaited artists into the fold of Magic, and even a few folks back
First introduced back in Scars of Mirrodin, proliferate was used to multiply not only -1/-1 counters on creatures or loyalty counters on planeswalkers, but also poison counters on players to provide an alternate win condition
While your emerald cards want to be challenged by your opponent to activate their abilities, ruby specializes in rewarding you for taking the fight to your opponent for a good balance
Id love one for my Commander deck, but not at this price, sadly
As always, Wizards of the Coast has sorted all of them by color, so you should be able to get a pretty good idea of just what each of the color pairs and deck archetypes are trying to do
I would make sure I have taken out all non-land permanents before I cast this, and then it can go for the lands