This will probably drop a fair amount in the coming weeks, but I imagine EDH will keep the price respectable
Notably if you can get this creature onto the battlefield without casting it, for example reanimating it from your graveyard, you wont have to sacrifice a creature
Mondrak, Glory Dominus's ability to double any token that's created under your control justifies the high price, but it becomes an even more fiscally sound investment when it gives itself an indestructible counter to become an unmovable threat
Quickly glancing at the numbers, it appears these fat packs are worth about 1/3 the cost of the corresponding sets booster box prices
While the life loss and gain synergy provides incremental advantage, there are better cards with similar effects, such as Zulaport Cutthroat or Blood Artist, which have lower mana costs and provide more immediate impact
While the ban list might look quite long at first glance, its really quite small when you consider the tens of thousands of cards that you can play there