While Spell/Trap card floodgates are easy to deal with because of cards like Lightning Storm and Twin Twisters, floodgate monsters are even more difficult to deal with, which makes Fossil Dyna Pachycephalo a useful card in a variety of situations
Without any modifications, it only takes three combat phases to deal enough poison counters to an opponent to make them lose the game
What Each Shop Does Best Not every collector needs the same thing
It could either kickstart the combo or extend it thanks to its effect to Special Summon itself if a Salamangreat monster was sent to the graveyard, while also being able to send a Salamangreat monster from the deck to the graveyard if it was Normal or Special Summoned
A Legendary Ocean This is the best Umi to use in the deck, both because it's the most searchable and because it allows us to Normal Summon Kairyu-Shin
Because of this, any card that can bring something out directly from the deck can become pretty valuable