Here is scenario in which NC wins 13 additional games (74 total) but does not reach the postseason.

Here are the final standings in the scenario:
            Team	W	L	D	PCT	GB
          Hanwha	84	57	3	0.5957	0.0
              LG	80	61	3	0.5674	4.0
         Samsung	77	65	2	0.5423	7.5
              KT	75	64	5	0.5396	8.0
             SSG	75	64	5	0.5396	8.0
              NC	74	64	6	0.5362	8.5
           Lotte	65	71	8	0.4779	16.5
             KIA	63	77	4	0.4500	20.5
          Doosan	60	77	7	0.4380	22.0
          Kiwoom	43	96	5	0.3094	40.0

To construct the scenario, we start with the current standings:
            Team	W	L	D	GL	PCT	GB
              LG	80	49	3	12	0.620	0.0
          Hanwha	76	53	3	12	0.589	4.0
             SSG	65	60	4	15	0.520	13.0
              KT	65	63	4	12	0.508	14.5
         Samsung	66	64	2	12	0.508	14.5
           Lotte	63	64	6	11	0.496	16.0
              NC	61	62	6	15	0.496	16.0
             KIA	61	65	4	14	0.484	17.5
          Doosan	56	70	6	12	0.444	22.5
          Kiwoom	43	86	4	11	0.333	37.0

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	-	0	0	3	0	1	0	0	0	0	4
Hanwha	1	-	3	1	0	3	0	0	0	0	8
KIA	0	0	-	1	0	0	1	0	0	0	2
Kiwoom	0	0	0	-	0	0	0	0	0	0	0
KT	0	2	1	1	-	4	0	0	1	1	10
LG	0	0	0	0	0	-	0	0	0	0	0
Lotte	0	1	0	0	0	1	-	0	0	0	2
NC	1	0	4	1	1	2	2	-	0	2	13
Samsung	1	0	2	2	0	1	3	1	-	1	11
SSG	4	1	2	1	0	0	1	1	0	-	10
-----------------------------------------------------------------------------------
Losses	7	4	12	10	1	12	7	2	1	4

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

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	-	8	6	12	4	7	7	5	6	5	60
Hanwha	7	-	12	14	9	8	9	9	8	8	84
KIA	9	4	-	8	8	5	9	6	7	7	63
Kiwoom	4	2	6	-	5	7	4	5	4	6	43
KT	11	7	8	11	-	8	6	6	11	7	75
LG	9	7	11	9	8	-	9	8	9	10	80
Lotte	7	7	7	11	8	5	-	7	7	6	65
NC	9	6	10	10	9	8	9	-	7	6	74
Samsung	10	8	9	12	5	7	8	9	-	9	77
SSG	11	8	8	9	8	6	10	9	6	-	75
-----------------------------------------------------------------------------------
Losses	77	57	77	96	64	61	71	64	65	64

					Scenario Total Draws (Ties) With
Team	Doosan	Hanwha	KIA	Kiwoom	KT	LG	Lotte	NC	Samsung	SSG	Total
Doosan	-	1	1	0	1	0	2	2	0	0	7
Hanwha	0	-	0	0	0	1	0	1	0	0	3
KIA	0	0	-	2	0	0	0	0	0	1	4
Kiwoom	0	0	0	-	0	0	1	1	0	1	5
KT	0	0	0	0	-	0	2	1	0	1	5
LG	0	0	0	0	0	-	2	0	0	0	3
Lotte	1	0	0	1	0	0	-	0	1	0	8
NC	0	0	0	0	0	0	0	-	0	1	6
Samsung	0	0	0	0	0	0	0	0	-	1	2
SSG	0	0	0	0	1	0	0	0	0	-	5
-----------------------------------------------------------------------------------
Total	7	3	4	5	5	3	8	6	2	5