How is hydra on jax

nah, if your goal split pushing a dueling. (which is what Jax usually does) Tri force and BotRK is way better. They really give you all the damage you need.

if you face multiple melees and plan to teamfight, the aoe can really help alot, but usually you try to splitpush, in which case other options are better.

or is better for Jax