diff --git a/src/Bladeburner/Actions/BlackOperation.ts b/src/Bladeburner/Actions/BlackOperation.ts
index 2780f3831..fd75cd469 100644
--- a/src/Bladeburner/Actions/BlackOperation.ts
+++ b/src/Bladeburner/Actions/BlackOperation.ts
@@ -5,6 +5,7 @@ import { BladeburnerActionType, BladeburnerBlackOpName } from "@enums";
 import { ActionClass, ActionParams } from "./Action";
 import { operationSkillSuccessBonus, operationTeamSuccessBonus } from "./Operation";
 import { getEnumHelper } from "../../utils/EnumHelper";
+import type { TeamActionWithCasualties } from "./TeamCasualties";
 
 interface BlackOpParams {
   name: BladeburnerBlackOpName;
@@ -12,7 +13,7 @@ interface BlackOpParams {
   n: number;
 }
 
-export class BlackOperation extends ActionClass {
+export class BlackOperation extends ActionClass implements TeamActionWithCasualties {
   readonly type: BladeburnerActionType.BlackOp = BladeburnerActionType.BlackOp;
   readonly name: BladeburnerBlackOpName;
   n: number;
@@ -57,6 +58,10 @@ export class BlackOperation extends ActionClass {
     return 1;
   }
 
+  getMinimumCasualties(): number {
+    return 1;
+  }
+
   getTeamSuccessBonus = operationTeamSuccessBonus;
 
   getActionTypeSkillSuccessBonus = operationSkillSuccessBonus;
diff --git a/src/Bladeburner/Actions/Operation.ts b/src/Bladeburner/Actions/Operation.ts
index b619d0643..614839d09 100644
--- a/src/Bladeburner/Actions/Operation.ts
+++ b/src/Bladeburner/Actions/Operation.ts
@@ -6,17 +6,18 @@ import type { ActionIdFor, Availability, SuccessChanceParams } from "../Types";
 import { BladeburnerActionType, BladeburnerMultName, BladeburnerOperationName } from "@enums";
 import { BladeburnerConstants } from "../data/Constants";
 import { ActionClass } from "./Action";
-import { Generic_fromJSON, IReviverValue, constructorsForReviver } from "../../utils/JSONReviver";
+import { constructorsForReviver, Generic_fromJSON, IReviverValue } from "../../utils/JSONReviver";
 import { LevelableActionClass, LevelableActionParams } from "./LevelableAction";
 import { clampInteger } from "../../utils/helpers/clampNumber";
 import { getEnumHelper } from "../../utils/EnumHelper";
+import type { TeamActionWithCasualties } from "./TeamCasualties";
 
 export interface OperationParams extends LevelableActionParams {
   name: BladeburnerOperationName;
   getAvailability?: (bladeburner: Bladeburner) => Availability;
 }
 
-export class Operation extends LevelableActionClass {
+export class Operation extends LevelableActionClass implements TeamActionWithCasualties {
   readonly type: BladeburnerActionType.Operation = BladeburnerActionType.Operation;
   readonly name: BladeburnerOperationName;
   teamCount = 0;
@@ -44,6 +45,10 @@ export class Operation extends LevelableActionClass {
 
   getActionTypeSkillSuccessBonus = operationSkillSuccessBonus;
 
+  getMinimumCasualties(): number {
+    return 0;
+  }
+
   getChaosSuccessFactor(inst: Bladeburner /*, params: ISuccessChanceParams*/): number {
     const city = inst.getCurrentCity();
     if (city.chaos > BladeburnerConstants.ChaosThreshold) {
diff --git a/src/Bladeburner/Actions/TeamCasualties.ts b/src/Bladeburner/Actions/TeamCasualties.ts
new file mode 100644
index 000000000..1f9724f74
--- /dev/null
+++ b/src/Bladeburner/Actions/TeamCasualties.ts
@@ -0,0 +1,47 @@
+export enum CasualtyFactor {
+  LOW_CASUALTIES = 0.5, // 50%
+  HIGH_CASUALTIES = 1, // 100%
+}
+
+export interface OperationTeam {
+  /** teamSize = Human Team + Supporting Sleeves */
+  teamSize: number;
+  teamLost: number;
+  /** number of supporting sleeves at time of action completion */
+  sleeveSize: number;
+
+  getTeamCasualtiesRoll(low: number, high: number): number;
+
+  killRandomSupportingSleeves(sleeveDeaths: number): void;
+}
+
+export interface TeamActionWithCasualties {
+  teamCount: number;
+
+  getMinimumCasualties(): number;
+}
+
+/**
+ * Some actions (Operations and Black Operations) use teams for success bonus
+ * and may result in casualties, reducing the player's hp, killing team members
+ * and killing sleeves (to shock them, sleeves are immortal) *
+ */
+export function resolveTeamCasualties(action: TeamActionWithCasualties, team: OperationTeam, success: boolean) {
+  const severity = success ? CasualtyFactor.LOW_CASUALTIES : CasualtyFactor.HIGH_CASUALTIES;
+  const radius = action.teamCount * severity;
+  const worstCase = severity < 1 ? Math.ceil(radius) : Math.floor(radius);
+  /** Best case is always no deaths */
+  const deaths = team.getTeamCasualtiesRoll(action.getMinimumCasualties(), worstCase);
+  const humans = action.teamCount - team.sleeveSize;
+  const humanDeaths = Math.min(humans, deaths);
+  /** Supporting Sleeves take damage when they are part of losses,
+   *   e.g. 8 sleeves + 3 team members with 4 losses -> 1 sleeve takes damage */
+  team.killRandomSupportingSleeves(deaths - humanDeaths);
+
+  /** Clamped, bugfix for PR#1659
+   * "BUGFIX: Wrong team size when all team members die in Bladeburner's action" */
+  team.teamSize = Math.max(team.teamSize - humanDeaths, team.sleeveSize);
+  team.teamLost += deaths;
+
+  return deaths;
+}
diff --git a/src/Bladeburner/Bladeburner.ts b/src/Bladeburner/Bladeburner.ts
index e3190ec8e..b55b833f1 100644
--- a/src/Bladeburner/Bladeburner.ts
+++ b/src/Bladeburner/Bladeburner.ts
@@ -37,7 +37,6 @@ import { Settings } from "../Settings/Settings";
 import { formatTime } from "../utils/helpers/formatTime";
 import { joinFaction } from "../Faction/FactionHelpers";
 import { isSleeveInfiltrateWork } from "../PersonObjects/Sleeve/Work/SleeveInfiltrateWork";
-import { isSleeveSupportWork } from "../PersonObjects/Sleeve/Work/SleeveSupportWork";
 import { WorkStats, newWorkStats } from "../Work/WorkStats";
 import { getEnumHelper } from "../utils/EnumHelper";
 import { PartialRecord, createEnumKeyedRecord, getRecordEntries } from "../Types/Record";
@@ -50,10 +49,12 @@ import { GeneralActions } from "./data/GeneralActions";
 import { PlayerObject } from "../PersonObjects/Player/PlayerObject";
 import { Sleeve } from "../PersonObjects/Sleeve/Sleeve";
 import { autoCompleteTypeShorthand } from "./utils/terminalShorthands";
+import { resolveTeamCasualties, type OperationTeam } from "./Actions/TeamCasualties";
+import { shuffleArray } from "../Infiltration/ui/BribeGame";
 
 export const BladeburnerPromise: PromisePair<number> = { promise: null, resolve: null };
 
-export class Bladeburner {
+export class Bladeburner implements OperationTeam {
   numHosp = 0;
   moneyLost = 0;
   rank = 0;
@@ -102,6 +103,7 @@ export class Bladeburner {
   automateThreshLow = 0;
   consoleHistory: string[] = [];
   consoleLogs: string[] = ["Bladeburner Console", "Type 'help' to see console commands"];
+  getTeamCasualtiesRoll = getRandomIntInclusive;
 
   constructor() {
     this.contracts = createContracts();
@@ -750,32 +752,20 @@ export class Bladeburner {
     }
   }
 
+  killRandomSupportingSleeves(n: number) {
+    const sup = [...Player.sleevesSupportingBladeburner()]; // Explicit shallow copy
+    shuffleArray(sup);
+    sup.slice(0, Math.min(sup.length, n)).forEach((sleeve) => sleeve.kill());
+  }
+
   completeOperation(success: boolean): void {
     if (this.action?.type !== BladeburnerActionType.Operation) {
       throw new Error("completeOperation() called even though current action is not an Operation");
     }
     const action = this.getActionObject(this.action);
-
-    // Calculate team losses
-    const teamCount = action.teamCount;
-    if (teamCount >= 1) {
-      const maxLosses = success ? Math.ceil(teamCount / 2) : Math.floor(teamCount);
-      const losses = getRandomIntInclusive(0, maxLosses);
-      this.teamSize -= losses;
-      if (this.teamSize < this.sleeveSize) {
-        const sup = Player.sleeves.filter((x) => isSleeveSupportWork(x.currentWork));
-        for (let i = 0; i > this.teamSize - this.sleeveSize; i--) {
-          const r = Math.floor(Math.random() * sup.length);
-          sup[r].takeDamage(sup[r].hp.max);
-          sup.splice(r, 1);
-        }
-        // If this happens, all team members died and some sleeves took damage. In this case, teamSize = sleeveSize.
-        this.teamSize = this.sleeveSize;
-      }
-      this.teamLost += losses;
-      if (this.logging.ops && losses > 0) {
-        this.log("Lost " + formatNumberNoSuffix(losses, 0) + " team members during this " + action.name);
-      }
+    const deaths = resolveTeamCasualties(action, this, success);
+    if (this.logging.ops && deaths > 0) {
+      this.log("Lost " + formatNumberNoSuffix(deaths, 0) + " team members during this " + action.name);
     }
 
     const city = this.getCurrentCity();
@@ -992,9 +982,7 @@ export class Bladeburner {
           this.stamina = 0;
         }
 
-        // Team loss variables
-        const teamCount = action.teamCount;
-        let teamLossMax;
+        let deaths;
 
         if (action.attempt(this, person)) {
           retValue = this.getActionStats(action, person, true);
@@ -1004,7 +992,8 @@ export class Bladeburner {
             rankGain = addOffset(action.rankGain * currentNodeMults.BladeburnerRank, 10);
             this.changeRank(person, rankGain);
           }
-          teamLossMax = Math.ceil(teamCount / 2);
+
+          deaths = resolveTeamCasualties(action, this, true);
 
           if (this.logging.blackops) {
             this.log(
@@ -1028,7 +1017,8 @@ export class Bladeburner {
               this.moneyLost += cost;
             }
           }
-          teamLossMax = Math.floor(teamCount);
+
+          deaths = resolveTeamCasualties(action, this, false);
 
           if (this.logging.blackops) {
             this.log(
@@ -1042,26 +1032,10 @@ export class Bladeburner {
 
         this.resetAction(); // Stop regardless of success or fail
 
-        // Calculate team losses
-        if (teamCount >= 1) {
-          const losses = getRandomIntInclusive(1, teamLossMax);
-          this.teamSize -= losses;
-          if (this.teamSize < this.sleeveSize) {
-            const sup = Player.sleeves.filter((x) => isSleeveSupportWork(x.currentWork));
-            for (let i = 0; i > this.teamSize - this.sleeveSize; i--) {
-              const r = Math.floor(Math.random() * sup.length);
-              sup[r].takeDamage(sup[r].hp.max);
-              sup.splice(r, 1);
-            }
-            // If this happens, all team members died and some sleeves took damage. In this case, teamSize = sleeveSize.
-            this.teamSize = this.sleeveSize;
-          }
-          this.teamLost += losses;
-          if (this.logging.blackops) {
-            this.log(
-              `${person.whoAmI()}:  You lost ${formatNumberNoSuffix(losses, 0)} team members during ${action.name}.`,
-            );
-          }
+        if (this.logging.blackops && deaths > 0) {
+          this.log(
+            `${person.whoAmI()}:  You lost ${formatNumberNoSuffix(deaths, 0)} team members during ${action.name}.`,
+          );
         }
         break;
       }
diff --git a/src/Infiltration/ui/BribeGame.tsx b/src/Infiltration/ui/BribeGame.tsx
index 7c4ffe5bf..8c737648d 100644
--- a/src/Infiltration/ui/BribeGame.tsx
+++ b/src/Infiltration/ui/BribeGame.tsx
@@ -12,6 +12,7 @@ import { KeyHandler } from "./KeyHandler";
 
 interface Difficulty {
   [key: string]: number;
+
   timer: number;
   size: number;
 }
@@ -106,7 +107,7 @@ export function BribeGame(props: IMinigameProps): React.ReactElement {
   );
 }
 
-function shuffleArray(array: string[]): void {
+export function shuffleArray(array: unknown[]): void {
   for (let i = array.length - 1; i > 0; i--) {
     const j = Math.floor(Math.random() * (i + 1));
     const temp = array[i];
diff --git a/src/PersonObjects/Player/PlayerObject.ts b/src/PersonObjects/Player/PlayerObject.ts
index 5e1eb07c4..818b714c0 100644
--- a/src/PersonObjects/Player/PlayerObject.ts
+++ b/src/PersonObjects/Player/PlayerObject.ts
@@ -28,6 +28,7 @@ import { CONSTANTS } from "../../Constants";
 import { Person } from "../Person";
 import { isMember } from "../../utils/EnumHelper";
 import { PartialRecord } from "../../Types/Record";
+import { isSleeveSupportWork } from "../Sleeve/Work/SleeveSupportWork";
 
 export class PlayerObject extends Person implements IPlayer {
   // Player-specific properties
@@ -171,6 +172,10 @@ export class PlayerObject extends Person implements IPlayer {
     return "Player";
   }
 
+  sleevesSupportingBladeburner(): Sleeve[] {
+    return this.sleeves.filter((s) => isSleeveSupportWork(s.currentWork));
+  }
+
   /** Serialize the current object to a JSON save state. */
   toJSON(): IReviverValue {
     return Generic_toJSON("PlayerObject", this);
diff --git a/src/PersonObjects/Sleeve/Sleeve.ts b/src/PersonObjects/Sleeve/Sleeve.ts
index 696d0f3bb..13d6d5d2a 100644
--- a/src/PersonObjects/Sleeve/Sleeve.ts
+++ b/src/PersonObjects/Sleeve/Sleeve.ts
@@ -536,6 +536,11 @@ export class Sleeve extends Person implements SleevePerson {
     return "sleeves";
   }
 
+  /** Sleeves are immortal, but we damage them for max hp so they get shocked */
+  kill() {
+    return this.takeDamage(this.hp.max);
+  }
+
   takeDamage(amt: number): boolean {
     if (typeof amt !== "number") {
       console.warn(`Player.takeDamage() called without a numeric argument: ${amt}`);
diff --git a/test/jest/Bladeburner/TeamCasualties.test.ts b/test/jest/Bladeburner/TeamCasualties.test.ts
new file mode 100644
index 000000000..45c3c17c7
--- /dev/null
+++ b/test/jest/Bladeburner/TeamCasualties.test.ts
@@ -0,0 +1,171 @@
+import { Player, setPlayer } from "@player";
+import { FormatsNeedToChange } from "../../../src/ui/formatNumber";
+import type { ActionIdFor } from "../../../src/Bladeburner/Types";
+import type { Bladeburner } from "../../../src/Bladeburner/Bladeburner";
+import { BlackOperation, Contract, Operation } from "../../../src/Bladeburner/Actions";
+import { Sleeve } from "../../../src/PersonObjects/Sleeve/Sleeve";
+import { SleeveSupportWork } from "../../../src/PersonObjects/Sleeve/Work/SleeveSupportWork";
+import { BladeburnerBlackOpName, BladeburnerContractName, BladeburnerOperationName } from "@enums";
+import { PlayerObject } from "../../../src/PersonObjects/Player/PlayerObject";
+
+/**
+ * You may want to use hook to help with debugging
+ * <code>
+ *   afterEach(() => {
+ *     console.error(inst.consoleLogs);
+ *   });
+ * </code>
+ */
+describe("Bladeburner Team", () => {
+  const MAX_ROLL = (_: number, high: number) => high;
+  const MIN_ROLL = (low: number, _: number) => low;
+  const BLACK_OP = BlackOperation.createId(BladeburnerBlackOpName.OperationAnnihilus);
+  const OP = Operation.createId(BladeburnerOperationName.Assassination);
+
+  let inst: Bladeburner;
+  let action: BlackOperation | Operation;
+
+  beforeAll(() => {
+    /* Initialise Formatters. Dependency of Bladeburner */
+    FormatsNeedToChange.emit();
+  });
+
+  beforeEach(() => {
+    setPlayer(new PlayerObject());
+    Player.init();
+    Player.startBladeburner();
+
+    if (!Player.bladeburner) throw new Error();
+    inst = Player.bladeburner;
+
+    Player.sourceFiles.set(10, 3);
+    Player.sleevesFromCovenant = 5;
+    Sleeve.recalculateNumOwned();
+    Player.sleeves.forEach((s) => (s.shock = 0));
+  });
+
+  describe("Operations", () => {
+    it("hav a chance of zero deaths for Operations", () => {
+      teamSize(10), startAction(OP), teamUsed(10), forceMinCasualties();
+      actionFails();
+      expect(inst.teamSize).toBe(10);
+    });
+  });
+
+  describe("Black Operations", () => {
+    it("always have at least 1 death", () => {
+      teamSize(10), startAction(BLACK_OP), teamUsed(10), forceMinCasualties();
+      actionFails();
+      expect(inst.teamSize).toBe(9);
+    });
+  });
+
+  describe("Solo: with no members or sleeves", () => {
+    it.each([
+      ["success", actionSucceeds],
+      ["fail", actionFails],
+    ])("remains unchanged at all rates: %s", (_: string, attempt: CallableFunction) => {
+      teamSize(1000), startAction(OP), teamUsed(0);
+      attempt();
+      expect(inst.teamSize).toBe(1000);
+    });
+  });
+
+  describe("Human members", () => {
+    it("get killed according to roll", () => {
+      teamSize(15), startAction(OP), teamUsed(15), forceMaxCasualties(), actionSucceeds();
+      expect(inst).toMatchObject({ teamSize: 7, teamLost: 8 });
+    });
+  });
+
+  describe("Assigned team members", () => {
+    it("get killed with human casualties before sleeves", () => {
+      /** At most 10 + 8 -> 9 casualties occur at worst,
+       * killing human team members before sleeves */
+      teamSize(10), startAction(BLACK_OP), supportingSleeves(8), teamUsed(18);
+      actionSucceeds();
+      expect(inst.teamSize).toBeLessThanOrEqual(18);
+      assertNoShockIncrease();
+    });
+
+    it("shocks sleeves when deaths exceed humans", () => {
+      teamSize(0), startAction(OP), supportingSleeves(8), forceMaxCasualties(), teamUsed(8);
+      actionFails();
+      assertSleevesHaveBeenShocked();
+    });
+  });
+
+  describe("Casualties", () => {
+    it("do not affect contracts", () => {
+      teamSize(3);
+      inst.action = Contract.createId(BladeburnerContractName.Tracking);
+      actionFails();
+      expect(inst.teamSize).toBe(3);
+    });
+
+    it.each([[OP], [BLACK_OP]])(
+      "will occur on actions that support teams: %s",
+      (op: ActionIdFor<BlackOperation> | ActionIdFor<Operation>) => {
+        teamSize(5), startAction(op), forceMaxCasualties(), teamUsed(5), actionFails();
+        expect(inst.teamSize).toBe(0);
+      },
+    );
+
+    it("are potentially entire team when failing", () => {
+      teamSize(5), startAction(OP), forceMaxCasualties(), teamUsed(5), actionFails();
+      expect(inst).toMatchObject({ teamSize: 0, teamLost: 5 });
+    });
+
+    it("at worst half the team when succeeding (rounding up)", () => {
+      teamSize(5), startAction(OP), forceMaxCasualties(), teamUsed(5), actionSucceeds();
+      expect(inst).toMatchObject({ teamSize: 2, teamLost: 3 });
+    });
+  });
+
+  function teamSize(n: number) {
+    inst.teamSize = n;
+  }
+
+  function teamUsed(n: number) {
+    action.teamCount = n;
+  }
+
+  function startAction(type: ActionIdFor<BlackOperation> | ActionIdFor<Operation>) {
+    inst.action = type;
+    action = inst.getActionObject(type) as BlackOperation | Operation;
+  }
+
+  function forceMaxCasualties() {
+    inst.getTeamCasualtiesRoll = MAX_ROLL;
+  }
+
+  function forceMinCasualties() {
+    inst.getTeamCasualtiesRoll = MIN_ROLL;
+  }
+
+  function actionSucceeds() {
+    action.baseDifficulty = 0;
+    Player.skills.strength = 1e12;
+    Player.skills.agility = 1e12;
+    inst.action && inst.completeAction(Player, inst.action);
+  }
+
+  function actionFails() {
+    action.baseDifficulty = 1e15;
+    inst.action && inst.completeAction(Player, inst.action);
+  }
+
+  function supportingSleeves(n: number) {
+    for (let i = 0; i < n; i++) Player.sleeves[i].startWork(new SleeveSupportWork());
+  }
+
+  function assertNoShockIncrease() {
+    const shockIncrease = Player.sleeves.reduce((sum, s) => sum + s.shock, 0);
+    expect(shockIncrease).toBe(0);
+  }
+
+  function assertSleevesHaveBeenShocked() {
+    const shockIncrease = Player.sleeves.reduce((sum, s) => sum + s.shock, 0);
+    expect(shockIncrease).toBeGreaterThan(0);
+  }
+});