If you place a boss on 1st slot you will receive automatically 25% boss loot bonus. The left 175% you must grind through hunting bosses.
Below I'm attaching a table with neccessary boss points to achieve the goal.
% boss loot bonus | Bosstiary Points |
27% | 20 |
28% | 30 |
29% | 40 |
30% | 50 |
31% | 60 |
32 | 70 |
33 | 80 |
34 | 90 |
35 | 100 |
36 | 110 |
37 | 120 |
38 | 130 |
39 | 140 |
40 | 150 |
41 | 160 |
42 | 170 |
43 | 180 |
44 | 190 |
45 | 200 |
46 | 210 |
47 | 220 |
48 | 230 |
49 | 240 |
50 | 250 |
51 | 270 |
52 | 290 |
53 | 310 |
54 | 330 |
55 | 350 |
56 | 370 |
57 | 390 |
58 | 410 |
59 | 430 |
60 | 450 |
61 | 470 |
62 | 490 |
63 | 510 |
64 | 530 |
65 | 550 |
66 | 570 |
67 | 590 |
68 | 610 |
69 | 630 |
70 | 650 |
71 | 670 |
72 | 690 |
73 | 710 |
74 | 730 |
75 | 750 |
76 | 770 |
77 | 790 |
78 | 810 |
79 | 830 |
80 | 850 |
81 | 870 |
82 | 890 |
83 | 910 |
84 | 930 |
85 | 950 |
86 | 970 |
87 | 990 |
88 | 1010 |
89 | 1030 |
90 | 1050 |
91 | 1070 |
92 | 1090 |
93 | 1110 |
94 | 1130 |
95 | 1150 |
96 | 1170 |
97 | 1190 |
98 | 1210 |
99 | 1230 |
100 | 1250 |
101 | 1275 |
102 | 1305 |
103 | 1340 |
104 | 1380 |
105 | 1425 |
106 | 1475 |
107 | 1530 |
108 | 1590 |
109 | 1655 |
110 | 1725 |
111 | 1800 |
112 | 1880 |
113 | 1965 |
114 | 2055 |
115 | 2150 |
116 | 2250 |
117 | 2355 |
118 | 2465 |
119 | 2580 |
120 | 2700 |
121 | 2825 |
122 | 2955 |
123 | 3090 |
124 | 3230 |
125 | 3375 |
126 | 3525 |
127 | 3680 |
128 | 3840 |
129 | 4005 |
130 | 4175 |
131 | 4350 |
132 | 4530 |
133 | 4715 |
134 | 4905 |
135 | 5100 |
136 | 5300 |
137 | 5505 |
138 | 5715 |
139 | 5930 |
140 | 6150 |
141 | 6375 |
142 | 6605 |
143 | 6840 |
144 | 7080 |
145 | 7325 |
146 | 7575 |
147 | 7830 |
148 | 8090 |
149 | 8355 |
150 | 8625 |
151 | 8900 |
152 | 9180 |
153 | 9465 |
154 | 9755 |
155 | 10050 |
156 | 10350 |
157 | 10655 |
158 | 10965 |
159 | 11280 |
160 | 11600 |
161 | 11925 |
162 | 12255 |
163 | 12590 |
164 | 12930 |
165 | 13275 |
166 | 13625 |
167 | 13980 |
168 | 14340 |
169 | 14705 |
170 | 15075 |
171 | 15450 |
172 | 15830 |
173 | 16215 |
174 | 16605 |
175 | 17000 |
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