Pop Cap has graciously created a pretty cool christmas event for their PvZ Heroes game. Each week there will be a card available and if you win enough tickets, you get a copy of that card, up to 4 copies.
It takes 2000 tickets for the first copy (1600, 1400 and 1200 respectively for the other copies) and you only get 15 tickets per multiplayer win though, so you might not be able to get all 4 copies. However, even if you are a moderate player, all is not lost because they have added a "boost" feature. Every 4 hours, certain avatars can get a 5x or 10x multiplier to get tickets. Throughout the day you should be able to reasonably use at least 4 of these boosts, so you should be getting at least 4x75 = 300 tickets every day for a total of 2100 over the week. That means you are guaranteed at least one copy of each card if you win at least 4 times every day over the course of the week. Since the games can be in casual, it should be fairly doable.
So that's pretty amazing already, we will be getting at least 1 event card (equivalent of super-rare) every week just for your basic casual playing. However, just with a bit more effort, you can certainly get 2-3 copies. If you get a few 10x heroes, that will double the number of tickets you get from boosts during that day and if you can get those 2 extra boosts (will likely need to set some alarms) you will also get a few hundred extra tickets.
Best of all, you can combine gems with tickets. The cards themselves cost 500 gems, but for each 200 tickets you have, 50 gems are deducted of the cost. There is an even better deal though, you can purchase an extra boost with 20 gems. When you have a 10x hero, that is essentially purchasing 135 tickets for 20 gems, which is a better exchange rate than the 200 tickets for 50 gems, so if you are bent on getting those cards but don't have all the time to win 50 games every day, I recommend waiting for when you do get that 10x hero and purchasing a few boosts and winning a few games (well, in this order: purchase a boost, win, purchase a boost, win, etc.).
You should take into account that there will be different cards each week for many upcoming weeks. Check out the Reddit pvz heroes for more info.
Also, it seems that tickets do not transfer between each week.
That's about it. Don't get too obsessed with the fact that you will likely be unable to get all the cards through grinding and without spending gems (only the most devoted players will do that), it's an event designed to give a high challenge to those who want the max prize, but a reasonable challenge for those who want to get the basic stuff, which is in this case one free copy of the card in question and, for most people, at least another copy.
