Here’s the full list of the Seasonal Legendaries, which as the name suggests, can only be found by ladder characters. The properties (and names, obviously) are subject to change during further PTR testing.

New Seasonal Legendaries
Bottomless Potion of Rejuvenation
•Restores 15% of your primary resource when used below 25% Life

Krelm’s Buff Belt

•Grants a 20% Movement Speed bonus
•Taking damage causes you to lose this effect for 15 seconds

Krelm’s Buff Bracers

•Grant you immunity to Knockback and Stun effects

x1_FollowerItem_Legendary_03 (Name still TBD)

•Equip on Follower: Reduces the cooldown of all Follower skills by 50%

Barbarian
Remorseless
Legendary one-handed Mighty Weapon

•Grants Hammer of the Ancients a 25-30% chance to summon an Ancient for 20 seconds

Crusader
P1_CruShield_norm_unique_01 (Name still TBD)
Legendary Crusader Shield

•Removes the cooldown of Condemn
•Condemn now costs 40 Wrath

Demon Hunter
Leonine Bow of Hashir
Legendary Bow

•Grants Bola Shot a 15-20% chance on explosion to pull in all enemies within 24 yards

Monk
Alabaster Gloves
Legendary Gloves

•Increases the duration of Sweeping Wind to 1 minute

Witch Doctor

•Seasonal Legendary not yet implemented

Wizard
p1_Wand_norm_unique_01 (Name still TBD)
Wand

•Removes the cooldown of Teleport
•Teleport now costs 25 Arcane Power

The plan is for a new batch of Seasonal Legendaries added each ladder season, and to become findable for all characters once the season ends. Then the next season will add more Seasonal Legenaries, so keep eyes on it.
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