Add arbitrary_points / Bonus points using API

omygoodness-You can achieve this using API V2.  There is no separate call for removing the bonus point, however, you can update it in negative value e.g if you want to revoke 100 points, you can send it in API V2 like this -100. 

PUT /community/2.0/mytenantid/users/42 HTTP/1.1
Host: api.lithium.com
Content-Type: application/json
Cache-Control: no-cache

{
    "data": {
        "type": "user",
        "biography": "I am the walrus.",
        "bonus_points": -100,
    }
}

https://community.lithium.com/t5/Developer-Documentation/bd-p/dev-doc-portal?section=commv2&collection=users#fields-bonus_points