This operation can be used after a black swan to bid collateral for taking over part of the debt and the settlement_fund (see BSIP-0018).
[ 38,{ "fee": { "amount": 0, "asset_id": "1.3.0" }, "bidder": "1.2.0", "additional_collateral": { "amount": 0, "asset_id": "1.3.0" }, "debt_covered": { "amount": 0, "asset_id": "1.3.0" }, "extensions": [] } ]