Mulligans
General Mulligans
In general, you would want to keep your card-generation cards like 'Illidari Studies' and 'Wandmaker' to get spells that could help you in your matchup. Drawing cards is also a key part of DH so cards like 'Chaos Strike' are good too.
Aggro Mulligans
Against aggro matchups, its important that you have early game removals. Illidari studies can be use to generate an 'Eye Beam' or a 'Consume Magic' to help you survive the early game. Having cheap minions like the 'Manafeeder' or 'Wandmaker' in the early game could also help to cool down early aggressive plays. Having your 'Warblades' ready in the early game could also help due to its lifesteal.
Midrange Mulligans
Mid ranged decks can be unpredictable at times, they could start off slow or even surprise you with an early aggressive play. Against these matchups you would want some early game removals as well as some draw to help you get to the cards you need.
Combo Mulligans
Against combo decks, you want to have an early aggressive play. It usually takes a lot of time for combo deck players to get their combo cards ready so having that early game pressure will help to disrupt their combo plays.

























