The type of cards you add and the amount will be determined by what your are trying to achieve, of course, but here are some general tips: When it comes to Pokmon, you normally want to have a main attacker and then some supporting ones that you can use depending on the matchup and the situation
A few noticeable Pokemon are missing (like Gengar) from the collection of SIRs and IRs, but most of the popular options are covered
In Commander, resolving one of these bad boys (or having one put into play via more nefarious means, such as with Muxus) is often enough for you to pull well ahead of your opponents on board
Mountain, Unhinged presents imposing peaks towering over a forest and lake near their base
The gold mewtwo card variants, which appear in certain premium sets and special collector tins, occupy a unique space in the catalog: they are not the rarest by print run, but the gold treatment makes them visually distinctive and consistently appealing to collectors who want the most striking version of the mewtwo card on their shelf or display