Some player-equipped projectile weapons cause the player to take damage when firing/throwing them at elephant cacti and some do not; this is not consistent even among weapons of the same type.
These weapons do not cause the player to take damage: Blow dart, harpoon, fire dart, boomerang, spear gun loaded with (normal) spear, spear gun loaded with battle spear.
These weapons do: Sleep dart, poison dart, spear gun loaded with poison spear, spear gun loaded with obsidian spear.
Steps to Reproduce
Attempt to use the listed weapons on an active elephant cactus.
Attempt to use the listed weapons on an active elephant cactus.
A developer has marked this issue as fixed. This means that the issue has been addressed in the current development build and will likely be in the next update.