Source: http://forums.trovegame.com/showthread.php?143973-PTS-Patch-Notes-3-26-2020

Additional Updates

• The "Ensnaring Grip" mutator -- which prevents mounting -- can no longer appear in Public and Private Delves, though it shall return in Challenge Mode!
• Drop rates for non-boss creatures in Delves have been increased.
• Adjusted delve gear drop rarity.
• Completing the path objectives (completing the steps required to activate the skull pile in the lair) will now reward XP.
• Updated the VFX for the following mounts: Moonbeam Gunship, Moonsail Glider, Balelight Flier.
• Added fins to Thrinky, the Delve ally.
• Shadow Towers now open directly to the boss lair, but there is an increased cost to open the portals.
• Delve Shadowkeys can now also be used in shadow towers, although using them in delves will give greater rewards.
• The number of rewards given from the Shadowy Soul Caches in delves has also been increased.
• Fixed gear drops from the delve chests to actually be above Epic rarity now.
• Added a new "Lifting of the Veil" Delve mutator for players at the lowest Depths. Good luck!
• The "Ensnaring Grip" mutator -- which prevents mounting -- can no longer appear in Public and Private Delves, though it shall return in Challenge Mode!... but for real this time!
• The leviathan chest should be able to be opened even if you die and release and are running back when the boss dies. Only people who actively participate in attacking the boss are eligible for loot.
• A new biome is now available (rarely) in Delves - Graveyard!