Toxiquake is a Spark that appears in Mario + Rabbids Sparks of Hope. It is first seen in the Darkmess Tentacle battle in Beacon Beach, named A Light in the Darkmess. After the battle, Toxiquake joins the Heroes on their adventure. Toxiquake is a large green Spark with the bottom half of its body covered in darker green toxic Ooze. Its appearance and ability are similar to Zephyrquake, Aquaquake, Electroquake and Cryoquake.

Source: https://www.mariowiki.com/Toxiquake