so after farming manyus and dragons the last days, i was able to start the event yesterday evening...
and lol, you're right. i thought you all were just exaggerating but i have already 9500 event currency and just killed the lvl22 boss. so it will be a piece of cake to clear the shop.
it will be a bit harder to get thru the lvl 50 boss thou. the lvl 20 boss was the first i needed 20 neckties. but the rewards for beating the bosses aren't bad:

->Open Spoiler<-

RB lvl	HP	BM	Reward
1	25,000	50
2	50,000	100
3	75,000	150
4	90,000	200
5	100,000	250
6	150,000	300
7	200,000	350
8	300,000	400
9	400,000	450
10	500,000	450
11	600,000	450
12	700,000	500
13	800,000	500
14	900,000	500
15	1,000,000	550
16	1,005,000	550
17	1,010,000	550
18	1,015,000	600
19	1,020,000	600
20	1,500,000	600
21	2,000,000	700
22	2,500,000	700
23	3,000,000
24
25
26
27
28
29
30
31			Life Crystals ×5
32			Coins ×10,000
33			Life Crystals ×5
34			Coins ×10,000
35			3x Ampy (1 of each Type)
36			Life Crystals ×5
37			Coins ×10,000
38			Life Crystals ×5
39			Coins ×10,000
40			4x Dragon (1 of each Type)
41			Life Crystals ×5
42			Coins ×10,000
43			Life Crystals ×5
44			Coins ×10,000
45			3x Ampy (1 of each Type)
46			Life Crystals ×5
47			Coins ×10,000
48			Life Crystals ×5
49			Coins ×50,000
50			3x Ampy (1 of each Type)