151c jumbo booster box Collect 151 Journey - Pokemon Pack - Simplified Chinese each containing 20 random cards CN 151 Surprise JUMBO Booster

Its an easy way to refill your deck with some Tearlaments cards you have used up already to prepare for the end game, or it can trigger Primeval Planet Perlereino

Three hasted copies of Ancient Brass Dragon doesnt sound bad

Diversify your purchases across at least 2-3 different sets and, ideally, across different formats (booster box + ETB)

This is where I feel that Pokemon has done a better job with re-prints

When you hear a Deck has a potential draw 4 + pop + Spell/Trap negate, with potentially ~20 slots for non-engine, that starts to sound like a real strategy

This is in line with previous Mega sets (except the first set)