Blackblood Drake and Swirling Tempest Rare Events.
Posting both together for easy reference. Both are extremely rare events in IPP which spawn these two rares as alternatives to the usual (at least) two known spawns of inside (and possibly outside) Howling Caves and Mage's Mark, in front of the house for Tempest, inside the Hermit cave for Drake.
Blackblood Drake event coords 4109 1723, this is the starting point - where the disk appears.
Note: Mad Hogger can also spawn at this loc as well as his (at least) two other spawns of inside (and possibly outside) Howling Caves and his junk pile at Mage's Mark.
Video shows first what happens if you choose wrong, then if you choose correct to arrive at the rare.
Note: I've had this despawn on me, whether a normal despawn from time, or due to 3 people doing it at once, or due to too many failures, I don't know. On that occasion, 1 person was waiting by the rare, 1 just got there and the 3rd was almost there. We all fell to our death.
Jumping off the final platform after the kill will simply loadscreen you to the start point unharmed.
Swirling Tempest event coords 3959 1715, this is the point the rare spawns at, the three disks spawn on the ice close by.
Video shows simply standing on all 3 disks in quick succession to spawn the rare.