As long as Hippowdon is your Active Pokémon, put 1 damage counter on each of your opponent's Pokémon LV.X between turns.

Save Sand

20+

Does 20 damage plus 10 more damage for each Energy attached to Hippowdon. Before doing damage, you may search your discard pile for a Fighting Energy card and attach it to Hippowdon.

Groundquake

80

Does 10 damage to each Benched Pokémon that isn't an Evolved Pokémon (both yours and your opponent's). (Don't apply Weakness and Resistance for Benched Pokémon).