Outside of the Stadium + Midfielder as your search each turn, your opponent will not know your main win condition or game plan until it is too late
Research Your Prices: While many of the specialist sites will provide tools to help you determine the average price for your cards, it is still worth researching your prices
Legendary Creature - Treefolk Color tag templates(None) Kyler, Sigardian Emissary Whenever another Human you control enters, put a +1/+1 counter on Kyler
Personally, I prefer the cards to be from the same set so they share the same overall design and set logo
There are references linked below to PokGyms rules forum, especially about this rule
The strength of your opponents increases as you progress, but your own Level increases also at a steady pace so you are always going to have a chance against the opponents, and whenever you battle a strong duelist for the first time, their Level is pretty close to yours, so the later duelists still offer a challenge the first time you duel against them