This is much easier to do online with a trading partner, though that is not required.
Online: Find a partner and have them whittle you down to one life, then win the game.
Offline: Once again, pound on some poor Suntail Hawks in the Disturbing the Nest encounter. This time, use the Born of Flame deck. Pause the game, and go to Help & Options. In Settings, tab over to Preferences, and turn off "Simplified Targeting." With this turned off, you can now damage yourself with your own magic, or target yourself with harmful abilities. Once the match is well in hand, torch yourself down to 1 life, and then win the game. Don't stress over the math as you can tap Prodigal Pyromancer to deal 1 damage to yourself per turn if you wish, which makes it easy to balance for how much damage the cards in your hand can do.