Praetor Slayer Challenge Mode ...
	Various Steam Achievements...

The Praetor Slayer achievement normally requires the player to successfully beat the challenge "Say Your Praetors" in five different ways -- each one requiring you to kill a different Praetor. However, thanks to this major glitch with the way the challenge works, you can easily unlock this achievement once you've discovered a method to kill any of the five. First, discover or look up any method of successfully completing the challenge. Now, go back into the challenge, but this time buff up your Baneslayer Angel any way you like so that she can kill one of the other Praetors on the defense. Once the Praetor has been killed, bring up the menu and select Restart Challenge to begin again. This time, pick another Praetor and kill it as before, then restart again. Repeat the above process until you've killed each color of Praetor once, then finish by restarting and completing the challenge successfully. When the win screen appears, you'll be informed that you've completed the achievement! If not in quite the way the developers intended.

Achievement	How to unlock
Archmage	Unlock 30 cards for one deck.
Auramancer	Win a duel controlling at least five Auras.
Avatar of Slaughter	Win a duel when an opponent controls no creatures.
Beast Within	Win a duel controlling a creature with at least 10 power.
Challenge Master	Solve ten challenges.
Dragon Slayer	Defeat Nicol Bolas in the revenge campaign.
Fearless Explorer	Defeat ten encounters.
Flawless	Win a campaign duel with 20 or more life.
Fury of the Horde	Win a duel controlling at least twenty creatures.
Guildmage	Defeat the Sepulchral Strength deck in the revenge campaign.
Insurrection	Win a duel online using an Expansion 1 deck.
Jack of All Trades	Unlock a card for each of ten different decks.
Last Mage Standing	Win a 3-player, 4-player, or Two-Headed Giant duel.
Maelstrom Wanderer	Win a Planechase campaign duel.
Magic: The Puzzling	Solve a challenge.
Master of the Wild Hunt	Win a duel controlling at least ten creatures.
Memory Adept	Enter the deck manager.
Mythic	Cast a mythic rare card.
Near-Death Experience	Win a duel with exactly 1 life.
Otherworldly Journey	Win a duel online.
Praetor Slayer	Solve the Say Your Praetors challenge in all five ways.
Savor the Moment	Win a campaign duel with an opponent's library empty.
Sky Summoner	Defeat Talrand in the campaign.
Time of Heroes	Defeat an encounter.
Two-Headed Giant	Win a Two-Headed Giant duel.