Hassleberry’s back with a “Collect items to spend at the Gate” event.

His rewards for beating him in Duels are:

Stegocyber (UR)
Evoltile Najasho (SR)
Miracle Jurassic Egg (SR)
Volcanic Eruption (SR)
Survival’s End (SR)
Frostosaurus (R)
Evo-Karma (R)
Evoltile Pleuro (R)
Evolsaur Terias (N)
Primordial Soup (N)

Evolsaur Diplo is a UR available via the EX Card Trader and through accumulating points in the Event.

And for his new event exclusive skill:

One with the Dinos
Can be used on turn 3 and onward. Select 1 Level 7 or higher Dinsaur-Type monster you control. Its ATK/DEF becomes equal to your Life Points.
When the selected monster leaves the field, you lose the Duel.
This Skill can only be used once per Duel.