You might be tempted to swap out Kotis for Muldrotha, and there is merit in doing so, but you can always bring Muldrotha back turn after turn with Kotis, and eventually, Kotis will outscale Muldrotha in terms of power once you cast two creatures from your graveyard, and will only keep growing
After completing Arenas tutorial, you get five starter packs
I got the Xerneas Battle Arena deck way back when and have been using and upgrading it ever since, but now that they aren't making any Fairy-type cards there's a hard limit to what value I can get from new expansions
If your extra deck needs a little fine tuning then look no further, as in this list were breaking down some extra deck staples worth looking into
Community forums and collectors groups
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