Unlike other Secret Lairs, the Extra Life Secret Lairs are all print to demand, so you'll always be able to obtain the drop so long as you order them in time
Last Counter X TRAP Counter When an attack is declared involving a "Battlin' Boxer" monster you control and an opponent's monster: Negate the attack, and if you do, send that monster you control to the GY, then 1 "Battlin' Boxer" monster you control (in Attack Position, if you declared the attack) gains ATK equal to the original ATK of that opponent's monster, also proceed to damage calculation using those monsters
We will update this article as soon as we see more reveals throughout the coming weeks, but so far, here is the complete card list, in Japanese
The mono-white deck uses Angel of Invention to plus up your creatures at the higher end along with Settle the Wreckage to wipe your opponent's board
3: You may put a Vampire creature card from your hand onto the battlefield