I haven't been back on this site for quite a while, but I can definitely say that this site seems to give out bad advice. Practically all UR cards are good for PvE, but chasing cards for older boxes is a bad idea for new players. Here's a more realistic list of staples:
World Legacy Clash
Cosmic Cyclone
Paleozoic Canadia
Drowning Mirror Force
Vermillion Dragon Mech
The best F2P deck for beginners to build aren't Yubel decks.
I would recommend Triamid as they are cost effective(though not as when Aliens were around) and yet easy enough for the beginner to utilise competitively enough. I do not recommend Darklords as you would likely have to spend 29000 gems, or Six Samurai for 34000 gems, while you can get Triamids for only 23000 gems or lesser.
If your'e an older player, I suggest you cut down on any gem spending and concentrate on accumulating gems.
Oh, wait, what about the staples issue? Sphere Kuriboh doesn't do much today except for PvE since the archetypes you are up against tend to be different compared to what we might face during sylvan era PvP. I would vouch for something similar for E-Con
Yeah, Yubel deck has the issue of the Yubel cards themselves being hard to obtain since Yubel is still not added to the Gate yet.
And to consistently farm Yubel for the cards, you'll need Masked Hero Vapor farming deck, which means you'll have to dig into Valiant Souls, in which case you might as well just play Masked-Destiny Heroes as your beginner deck.
Yang
Yang
