How about we keep the buffs to the hydra, but we bring gold back and MASSIVELY increase the drop rates of set pieces and red coins. A drop rate of about 1% for set pieces or atifact and 4-5% for red raid coin seems reasonable to me.

HOWEVER, we put a timer on the Hydra. What do I mean?

The Hydra shows up for only 30 mintues - 1 hour two times a day with these buffs, thus limiting the amount players can loot from it due to the time constraints. (not something like after a certain number of festerfang kills the boss unlocks, like every at 12 AM and 12PM central time, the boss shows up to be killed)

And to avoid time constraints to players in other countries, the times the Hydra spawns should rotate every day (12AM and 12PM, 1AM and 1PM, 2AM and 2PM, etc.)

It can be a lot like a world boss or raids Ive seen from other MMOs before.