KBO Magic (Tragic) Numbers

Rank / Team	PR	PS	PCT	PCT_max	PCT_min	Rank_max/min	G	G_rem	W	W_max	L	L_max	D
1 Kia Tigers	113 (120)	110 (123)	.714	.944	.139	1 / 10	28	116	20	136	8	124	0
2 NC Dinos	120 (113)	113 (119)	.607	.924	.118	1 / 10	28	116	17	133	11	127	0
3 SSG Landers	120 (112)	114 (118)	.571	.916	.112	1 / 10	29	115	16	131	12	127	1
3 Samsung Lions	120 (112)	114 (118)	.571	.916	.112	1 / 10	29	115	16	131	12	127	1
5 LG Twins	121 (110)	115 (116)	.536	.908	.106	1 / 10	30	114	15	129	13	127	2
6 Kiwoom Heroes	124 (110)	117 (115)	.481	.903	.090	1 / 10	27	117	13	130	14	131	0
7 Doosan Bears	123 (108)	116 (113)	.467	.889	.097	1 / 10	30	114	14	128	16	130	0
8 Hanwha Eagles	126 (107)	120 (112)	.393	.882	.076	1 / 10	28	116	11	127	17	133	0
9 KT Wiz	126 (105)	120 (109)	.345	.867	.070	1 / 10	30	114	10	124	19	133	1
10 Lotte Giants	128 (106)	122 (110)	.308	.874	.056	1 / 10	27	117	8	125	18	135	1

Magic and tragic (aka elimination) numbers are provided both for the pennant race (1st place) and postseason (5th place). For simplicity, this explainer will refer to the postseason numbers only (the competition for the #5 spot), but the others work the same way.
If a team's postseason magic number reaches zero, they are no longer in danger of being eliminated and are guaranteed a spot in the top 5. Conversely, if the team's postseason tragic (elimination) number reaches zero, they have been decisively eliminated and no longer have any chance of playing in the postseason.
A team's "magic number" decreases by one if the team wins, or if the next contending team loses. The "next contending team" is the team with the best chance of taking the 5th spot. This is typically the #6 team, but may not be, depending on how many draws and remaining games the other teams have.
If two teams in contention finish the regular season with an identical W-L-D record, they will play a tiebreaker game with no inning limit on the following day to determine the final standings. Their record against each other will determine where the game is played.
Note that the max/min rank numbers are calculated naively, based on best/worst case scenarios, where the best case scenario assumes that all other teams lose all of their remaining games. This is obviously impossible, but it is a necessary simplification for now, and in all but the closest contests, is accurate enough for our purposes.

#4 and #5 face off in a “best of 3 series” (Wild Card) in which the #4 team starts with a one win lead. In other words, either one or two games will be played: the #5 team must win two games to advance, whereas the #4 team can advance with just one win (or even a tie).
The winner of that series faces #3 in a best of 5 series (Semi-Playoff/준PO/준플레이오프).
The winner of that series faces #2 in a best of 5 series (Playoff/PO/프레이오프).
The winner of that series faces #1 in a best of 7 series known as the Korean Series (코시/한국시리즈).
A best of 5 series consists of two games at the higher-ranked team’s home, a travel day, two at the lower-ranked team’s home, another travel day, and the final game (if needed) at the higher-ranked team’s home.
The Korean Series schedule can vary, but typically consists of two games at the higher ranked team’s home, a travel day, three games at the lower-ranked team’s home, another travel day, and the final two games (if needed) at the higher ranked team’s home.