While most people were focused on the Lions Eye Diamonds and Lotus Vales of the world, Flash quietly picked up errata that basically made it so that you couldnt just pick a creature and not pay for it, so that you could do the enters the battlefield trick which was the exact trick the card was originally designed to allow for (albeit, long before they conceived of just how big of design constraints this could put on them in the future if they changed the types of creatures they made)
True Conviction, in particular, is a spell that single-handedly closes the door on games
Smashing your head off of brick walls is no fun, and Siege Rhino will only further complicate things by granting the wielder more life and draining their opponent
If going second, charging A2a-071 can be good since you can give 1 Energy to A2a-071 and manually attach 1 Energy into A2a-071, then next turn attach 1 more Energy enabling it to attack
Effect,Condition,Continuous
Anyway, for consistency, all booster packs came from the same set