Here is scenario in which Doosan makes the postseason with 33 additional wins (42 total).

Here are the final standings in the scenario:
            Team	W	L	D	PCT	GB
         Samsung	119	21	4	0.8500	0.0
              NC	117	23	4	0.8357	2.0
              LG	113	29	2	0.7958	7.0
              KT	105	38	1	0.7343	15.5
          Doosan	42	98	4	0.3000	77.0	See explanation of tie-breakers below.
          Kiwoom	42	98	4	0.3000	77.0	See explanation of tie-breakers below.
          Hanwha	42	99	3	0.2979	77.5
             KIA	42	100	2	0.2958	78.0
           Lotte	42	100	2	0.2958	78.0
             SSG	41	99	4	0.2929	78.0

Explanation of Tie-breakers:
Doosan and Kiwoom tie for fifth place and play a post-season game; the winner goes on to the wild-card game.

To construct the scenario, we start with the current standings:
            Team	W	L	D	GL	PCT	GB
              LG	17	4	0	123	0.810	0.0
           Lotte	12	10	1	121	0.545	5.5
          Hanwha	12	11	0	121	0.522	6.0
              KT	10	10	1	123	0.500	6.5
         Samsung	11	11	0	122	0.500	6.5
             SSG	9	10	0	125	0.474	7.0
          Doosan	9	11	0	124	0.450	7.5
             KIA	9	12	0	123	0.429	8.0
              NC	7	10	0	127	0.412	8.0
          Kiwoom	8	15	0	121	0.348	10.0

The next two tables show, respectively, how many of their remaining games each team wins and ties against each of the other teams in the scenario:

					Scenario Additional Wins Against
Team	Doosan	Hanwha	KIA	Kiwoom	KT	LG	Lotte	NC	Samsung	SSG	Wins
Doosan	-	1	0	11	0	0	13	0	0	8	33
Hanwha	12	-	8	7	0	0	3	0	0	0	30
KIA	15	5	-	0	0	0	13	0	0	0	33
Kiwoom	1	4	13	-	0	0	3	0	0	13	34
KT	13	14	13	15	-	0	13	13	0	14	95
LG	13	13	14	13	14	-	14	0	0	15	96
Lotte	0	10	0	10	0	0	-	0	0	10	30
NC	16	15	14	13	0	13	13	-	10	16	110
Samsung	13	13	14	14	14	12	15	0	-	13	108
SSG	4	13	12	0	0	0	3	0	0	-	32
-----------------------------------------------------------------------------------
Losses	87	88	88	83	28	25	90	13	10	89

					Scenario Additional Draws (Ties) With
Team	Doosan	Hanwha	KIA	Kiwoom	KT	LG	Lotte	NC	Samsung	SSG	Total
Doosan	-	0	0	2	0	0	0	0	0	2	4
Hanwha	0	-	0	2	0	0	1	0	0	0	3
KIA	0	0	-	0	0	0	0	0	0	2	2
Kiwoom	2	2	0	-	0	0	0	0	0	0	4
KT	0	0	0	0	-	0	1	0	0	0	0
LG	0	0	0	0	0	-	0	1	1	0	2
Lotte	0	1	0	0	0	0	-	0	0	0	1
NC	0	0	0	0	0	1	0	-	3	0	4
Samsung	0	0	0	0	0	1	0	3	-	0	4
SSG	2	0	2	0	0	0	0	0	0	-	4
-----------------------------------------------------------------------------------
Total	4	3	2	4	0	2	1	4	4	4

The next two tables show, respectively, how many total games each team wins and ties against each of the other teams in the scenario:

					Scenario Total Wins Against
Team	Doosan	Hanwha	KIA	Kiwoom	KT	LG	Lotte	NC	Samsung	SSG	Wins
Doosan	-	2	1	13	1	1	15	0	1	8	42
Hanwha	14	-	10	9	1	0	3	1	1	3	42
KIA	15	6	-	1	2	0	15	1	1	1	42
Kiwoom	1	5	15	-	1	1	3	1	0	15	42
KT	15	15	14	15	-	1	14	15	2	14	105
LG	15	16	16	15	15	-	16	2	2	16	113
Lotte	1	12	1	13	1	0	-	2	1	11	42
NC	16	15	15	15	1	13	14	-	12	16	117
Samsung	15	15	15	16	14	13	15	1	-	15	119
SSG	6	13	13	1	2	0	5	0	1	-	41
-----------------------------------------------------------------------------------
Losses	98	99	100	98	38	29	100	23	21	99

					Scenario Total Draws (Ties) With
Team	Doosan	Hanwha	KIA	Kiwoom	KT	LG	Lotte	NC	Samsung	SSG	Total
Doosan	-	0	0	2	0	0	0	0	0	2	4
Hanwha	0	-	0	2	0	0	1	0	0	0	3
KIA	0	0	-	0	0	0	0	0	0	2	2
Kiwoom	2	2	0	-	0	0	0	0	0	0	4
KT	0	0	0	0	-	0	1	0	0	0	1
LG	0	0	0	0	0	-	0	1	1	0	2
Lotte	0	1	0	0	0	0	-	0	0	0	2
NC	0	0	0	0	0	1	0	-	3	0	4
Samsung	0	0	0	0	0	1	0	3	-	0	4
SSG	2	0	2	0	0	0	0	0	0	-	4
-----------------------------------------------------------------------------------
Total	4	3	2	4	1	2	2	4	4	4

# Doosan Bears magic number
# Doosan's magic number
# Bears magic number
# KBO Playoff Race