bunnyKill.js

function bunnyKill(input) {
    let index = 0;
    let rows = input.reverse();
    let coordinates = rows[0].split(/,|\s/).map(Number);
    rows.reverse().pop();
    let snowBallDMG = 0;
    let snowBallC = 0;

    for (let i = 0; i < rows.length; i++) {
        rows.splice(i, 1, rows[i].split(' ').map(Number));
    }

    for (let row = 0; row < coordinates.length; row += 2) {
        let rowMatch = coordinates[index];
        index++;
        let columnMatch = coordinates[index];
        index++;
        if (rows[rowMatch][columnMatch] > 0) {
            let talibanBunny = rows[rowMatch][columnMatch];
            snowBallDMG += talibanBunny;
            snowBallC++;

            let explosionRange = [-1, -1, -1, 0, -1, 1, 0, -1, 0, 1, 1, -1, 1, 0, 1, 1];
            let i = 0;

            for (let range = 0; range < 8; range++) {
                let expRow = explosionRange[i];
                i++;
                let expColumn = explosionRange[i];
                i++;

                if (rows[rowMatch + expRow] !== undefined) {
                    if (rows[rowMatch + expRow][columnMatch + expColumn] !== undefined) {
                        let validExplosion = rows[rowMatch + expRow][columnMatch + expColumn];
                        validExplosion - talibanBunny >= 0 ? rows[rowMatch + expRow].splice(columnMatch + expColumn, 1, validExplosion - talibanBunny) : rows[rowMatch + expRow].splice(columnMatch + expColumn, 1, 0);
                    }
                }
            }
            rows[rowMatch].splice(columnMatch, 1, 0);
        }
    }

    for (let row of rows) {
        snowBallDMG += row.reduce((cellA, cellB) => cellA + cellB);
        for (let cell of row) {
            if (cell > 0) {
                snowBallC++;
            }
        }
    }
    console.log(snowBallDMG);
    console.log(snowBallC);
}

bunnyKill(['5 10 15 20',
    '10 10 10 10',
    '10 15 10 10',
    '10 10 10 10',
    '2,2 0,1']);

console.log('---');

bunnyKill(['10 10 10',
    '10 10 10',
    '10 10 10',
    '0,0']);