Once the Hydra is in play your other Hydras cost four generic mana less, which is huge, especially since you can apply that four generic mana to any X cost creatures
Similarly, while it's unlikely we'll "unbuff" cards that received balance adjustments to improve playability (and currently have no plans to do so), only a certain type of dark-empowered entity deals in absolutes, and we're not them
This means that the only types that are truly missing are Bug, Ghost, Ground, Flying, Ice, Poison, and Rock
Overall, Tearlament was an amazing archetype, and its options for winning the game were almost endless
It can always sacrifice itself as a one-shot proliferate effect too
The idea is to create a defensive fort around yourself, making you less of a target