Its prevention of life gain and prohibiting damage prevention is what makes it so scary - for some strategies, life gain or "fog" effects get them through scary turns against aggressive Red decks, which is no longer an option when Sunspine Lynx is in play
They appear about 25% of the time in the final card slot, and all rarities are represented, from common all the way up to mythic rare
Deckbuilding really is the most challenging part of a prerelease flight, so once you get that sorted you should be able to relax and breathe in the atmosphere
Collector Boosters bring the heat your players have been waiting for
However you do it, these sites provide excellent resources to get started
2 Modified - Mythic Theme Love Those Counters In a format where you want to overpower your opponents using a semi-fixed deck, anything that can give you the advantage is going to be key