Phial of Ravenous Slime
Drops from Vat of Conspicuous Slime. This appears to be working again. Hotfix on Nov.
The 
Phial of Ravenous Slime is a Shadowlands toy obtained in the House of Plagues area of Maldraxxus by interacting with an environmental object on a lab table.
Guide awaiting review
Travel to House of Plagues
Head to the House of Plagues in Maldraxxus. The area you need is narrowly south-east of the local flight master.
Find the Empty Plague Bottle
Locate a hut with a lab table inside. On the table you will find a clickable 
Empty Plague Bottle next to a green ooze pool. Pick up the bottle — the ooze pool will not be interactive until you do.
Click the Vat of Conspicuous Slime
Once you have the Empty Plague Bottle in hand, the green ooze pool — the Vat of Conspicuous Slime at 59.86, 79.07 in Maldraxxus — will become interactive with a cogwheel icon. Click it to receive the toy.
Locate It in Your Toy Box
If the toy does not appear in your collection after looting, open the Toys tab, uncheck all filters, then re-check the Collected filter to make it visible.
Tips
When used, the toy transforms you into a Red Slime for roughly 15–20 seconds, grants an 8-yard radius that absorbs nearby party members, and moves you and those inside you at nearly double mount speed — however, you cannot stop moving while transformed.
You and any party members absorbed inside you will take very minor damage per second while the transformation is active.
