Update 1.9.0 - 1.9.1: 

New spider forms have been released!

New Form

Spider forms introduce a new silk-based ability system, allowing players to shoot web projectiles, create climbable web structures, hinder enemies, and gain stronger mobility options in later stages.
Added Spider-exclusive trinkets/tools gameplay through extra hand slots with different special effects.

Improvements

For the Sinytra Connector version, the form-specific Trinkets are now compatible with Curios and can be placed directly in the Curios slot.
Improved codex readability with support for longer scrollable text.
Added more advancement guidance for discovering and collecting forms.
Added vanilla recipe unlocks for several vanilla-form accessories and tools.
Improved permanent spider form and feral forms' footstep behavior to better match the form’s movement style.

Bug Fixes

Fixed missing Spider form abilities, including missing sounds/night vision behavior.
Fixed spiders incorrectly attacking during the daytime.
Fixed several Spider-related item, slot, rendering, and compatibility issues.
Fixed a few crash issues that could occur in specific situations.
Fixed missing form text, ability entries, and localization keys.