First of all, sorry for posting in such an old post, but I've recently played this matchup as a beastmaster and this was pretty fun. It was also tough, but as we both aren't too good with the game, we made several mistakes and mine were just not that serious I guess
Necromancer started with dropping ring that gives his discounts and his evil book while I rushed to NC and put down a lair in FC. Next turn necromancer build 2 walls around his corner and started summoning small zombies using his book - he wanted to feed the Shagot Zara with them later (I'm almost sure that I'm spelling this wrong
. I harmonized my lair and summoned a falcon, while running further to his corner.
Then I started to summon wolves and broke though the wall, while necromancer built Idol of Pestilence, and summoned Malakoda together with Shagot Zara. So basically I was receiving 3 damage per turn just for standing near this guys. I focused down the Malacoda while attacking necro with my beastmaster, and when I finished it, he responded with Poison Cloud.
At this time his Shagot Zara had around 4 counters, but his mage was pretty hurt by my pet wolf with vampiric and bear strength. Wolf also got flying later in order to save it from massive zombies attacks. In the last round I teleported my mage from the danger zone and managed to finished mage with my flying wolf.
The matchup is definitely hard for beastmaster, as zombies are very hard to kill and Deathlock can destroy all your plans to save your creatures. I'm not sure what to do with fed Shagot Zara either, I just managed to kill necro fast enough, because his defenses were not strong enough. What benefits beastmaster is the fact that all zombies are bloodthirsty, so they can't guard if they feel any wounded creatures around.