public void gainXenonSurplus(short amount) {
        int maxSupply = level >= 100 ? 20 : level >= 60 ? 15 : level >= 30 ? 10 : 5;
        if (xenonSurplus + amount > maxSupply) {
            this.xenonSurplus = (short) maxSupply;
            updateXenonSurplus(xenonSurplus);
            return;
        }
        this.xenonSurplus += amount;
        updateXenonSurplus(xenonSurplus);
    }