In white, the go-to card is always going to be Swords to Plowshares
Although the deck has a horrible mana base, your opponents will have a very hard time stopping your dragons
If you do, each opponent loses 1 life and you gain that much life.) Artifacts and creatures your opponents control enter the battlefield tapped
Even better, you get to make another of these tokens every time the Overlord attacks, ramping you up over and over again
There are also special actions called Songs which can be played for free, provided you have a character of the required cost already on board that you can exert to "sing" the song
Small hands can make it tough to hold a ton of playing cards, so built simple DIY LEGO playing card holders for any card game