I would actually stick with Heavy Bone most of the time, unless you flipped a tail and were forced to you Bone Rush
Being able to reduce or remove Retreat Cost can make switching out cards much easier during a match, and only having to use 3 Lightning Energy to pull off a multi-attack like Multishot Lightning is unreal
As a land, the front face lacked a mana cost and would be considered a back face under the previous rules
Control Decks such as Snorlax Stall get access to Eri, a new supporter that allows you to look at your opponents hand and discard 2 item cards, getting rid of all their switching options
No one knows the exact number of 1st Edition cards, but it's been estimated that less 10,000 of each card was produced
Kokusho is huge as a 5/5 flier for 4BB, and when it dies, each opponent loses 5 life, and Kokusho's controller gains life equal to the total life lost