Experience

Level	Experience	Difference
1	0	N/A
2	1,000	N/A
3	2,000	100.0%
4	3,200	60.0%
5	4,600	43.8%
6	6,200	34.8%
7	8,000	29.0%
8	10,000	25.0%
9	12,200	22.0%
10	14,700	20.5%
11	17,500	19.0%
12	20,600	17.7%
13	24,320	18.1%
14	28,784	18.4%
15	34,140	18.6%
16	40,567	18.8%
17	48,279	19.0%
18	57,533	19.2%
19	68,637	19.3%
20	81,961	19.4%
21	97,949	19.5%
22	117,134	19.6%
23	140,156	19.7%
24	167,782	19.7%
25	200,933	19.8%
26	240,714	19.8%
27	288,451	19.8%
28	345,735	19.9%
29	414,475	19.9%
30	496,963	19.9%
31	595,948	19.9%
32	714,730	19.9%
33	857,268	19.9%
34	1,028,313	20.0%
35	1,233,567	20.0%
36	1,479,871	20.0%
37	1,775,435	20.0%
38	2,130,111	20.0%
39	2,555,722	20.0%
40	3,066,455	20.0%
41	3,679,334	20.0%
42	4,414,788	20.0%
43	5,297,332	20.0%
44	6,356,384	20.0%
45	7,627,246	20.0%
46	9,152,280	20.0%
47	10,982,320	20.0%
48	13,178,368	20.0%
49	15,813,625	20.0%
50	18,975,933	20.0%
51	22,770,702	20.0%
52	27,324,424	20.0%
53	32,788,890	20.0%
54	39,346,249	20.0%
55	47,215,079	20.0%
56	56,657,675	20.0%
57	67,988,790	20.0%
58	81,586,128	20.0%
59	97,902,933	20.0%
60	117,483,099	20.0%
61	140,979,298	20.0%
62	169,174,736	20.0%
63	203,009,261	20.0%
64	243,610,691	20.0%
65	292,332,407	20.0%
66	350,798,466	20.0%
67	420,957,736	20.0%
68	505,148,860	20.0%
69	606,178,208	20.0%
70	727,413,425	20.0%
71	872,895,685	20.0%
72	1,047,474,397	20.0%
73	1,256,968,851	20.0%
74	1,508,362,195	20.0%
75/88	1,810,034,207	20.0%

Experience is a measurement of hero's capability. Initially, every hired hero starts with a random number of experience in the range of 40 to 90 points. Experience is gained as heroes explore and battle. When they have enough experience points, they gain a level. Gaining a level may have several effects. It always increases one of the hero's primary skills by one. Hero classes have different probabilities of which primary skill is increased, but the general rule is that might heroes tend to get more attack and defense while magic heroes get more power and knowledge. Typically, when a hero gains a level, he or she is offered a choice of one of two secondary skills. Additionally, many of the hero specialties are affected at level up.

Typical ways for heroes to gain experience is through combat or from treasure chests. Additionally, Pandora's Boxes, Events and Quests can give experience. The Dungeon town has a special building, the Battle Scholar Academy, which gives 1,000 experience points to every visiting hero. There are also objects on the map which give experience: The Learning Stone gives 1,000 experience points, the Tree of Knowledge allows a hero to level-up and the Altar of Sacrifice allows to sacrifice creatures or artifacts for experience.

From winning a combat, the hero receives one experience point for each HP of the enemy creatures he managed to vanquish in the battle (clones, war machines and bonus health from artifacts do not count). Resurrected creatures are only counted once, except Demons raised by Pit Lords. If an enemy hero is defeated or an enemy town is captured during a siege, the hero receives 500 extra experience points. A hero will not receive this bonus if the enemy hero escapes or surrenders. If a hero escapes or surrenders, then that hero does not gain any experience, even if he/she managed to kill creatures from the victorious hero. A hero from whom the enemy hero escaped receives experience for the killed enemy creatures, but does not gain experience for the defeated hero.

Heroes with Learning gain extra experience.

Bug: after reaching level 75, a hero gets level 88 at once (13 more level-ups consecutively). From now on, the level-up mechanics shows highly unstable work, including the possibility of falling into an infinite loop of level-ups.

Horn of the Abyss

In Horn of the Abyss, the overflow of experience was fixed. Maximum possible hero level is 74.