You can switch in the cards in your side deck between duels in matches
Here is the thing: while Unstable has a ton of splashy, crazy cards and mondo-combos, down in the weeds there are all sorts of neat little synergies you can tap into to gain an edge
PSE Prismatic Secret Rare Berserker of the Tenyi X DARK Link 3 [ WyrmLink ] ATK 3000 DEF - 2+ monsters, including a Link Monster C Common Wynn the Wind Charmer, Verdant X WIND Link 2 [ SpellcasterLinkEffect ] ATK 1850 DEF - 2 monsters, including a WIND monster (This card is always treated as a "Familiar-Possessed" card.) You can target 1 WIND monster in your opponent's GY
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Rise and Shine is a nice way to turn your Clue and Food tokens, or any artifacts you have, into 4/4 creatures that can join the Dog pack for a big attack
Chandra, Torch of Defiance , Chandra, Fire Artisan , and Chandra, Pyromaster