Another puzzle for you. [Ended; solution posted]

Game: Alice: Madness Returns
Contributor: $0.99
Ends: Jun 18, 2012 7:00 a.m. GMT+4
Entries: 7

1) SHRyamNzZCBheGlpdGd4aCB0aGkgYXhpaXRncCBJ
Inf.: This hint ruled from 79 to 81 A.D.

2) R3N2IHVsZmlncyBvdmdndmkgaXZuenJtaCBmbXhzem10dncgdWlsbiBnc3YgeGxubmxtIGt6Z2d2aW0=
Inf.: This hint is mystical. And Jewish.

3) SyB1YSByZ3cgZHVlYXIga3dycndl
Inf.: This hint is right in front of you.

4) b3RlYmFmbGEnbGxlZCBhcmV0dGVsIGF0c2VzIGFsIOggYXJldHRlbCBhdG5pdVE=
Inf.: This hint can bring you bad luck.

5) VG1oYmVlIHJ0LmggaVdyaGRpIGNsaGUgdHl0b2V1ciAgd2lpc2wgbG4gb2h0YSB2YWUgIGx0ZW90IHRiZXJydSB0YmV1ZnRvIHJhYyBlbi51
Inf.: This hint skips a couple of steps but nothing else.

All letters are capital.

Go!

Solution:
Each message is base64 code + a different cipher. Extra info I gave should've helped you determine which cipher to use. And this site would've been a tremendous help.

1) Google "79-81 AD" and you'll get a lot of results for Emperor Titus. Who (if you count Gaius Julius) was 11th Caesar. So it's Caesar cipher, ROT11. And then translate from Latin.
SHRyamNzZCBheGlpdGd4aCB0aGkgYXhpaXRncCBJ --> Htrjcsd axiitgxh thi axiitgp I --> Secundo litteris est littera T --> The second letter is the letter T

2) Atbash cipher.
R3N2IHVsZmlncyBvdmdndmkgaXZuenJtaCBmbXhzem10dncgdWlsbiBnc3YgeGxubmxtIGt6Z2d2aW0= --> Gsv ulfigs ovggvi ivnzrmh fmxszmtvw uiln gsv xlnnlm kzggvim --> The fourth letter remains unchanged from the common pattern
Common pattern being XXXXX or xxxxx and since all letters are capital it's X.

3) Keyboard cipher. Just shift the letters one key to the right.
SyB1YSByZ3cgZHVlYXIga3dycndl --> K ua rgw duear kwrrwe --> L is the first letter.

4) This was supposed to be the mirror writing. But since you need pen, paper and mirror for the actual mirror writing, it's just a reversed string. In Italian.
b3RlYmFmbGEnbGxlZCBhcmV0dGVsIGF0c2VzIGFsIOggYXJldHRlbCBhdG5pdVE= --> otebafla'lled arettel atses al è arettel atniuQ --> Quinta lettera è la sesta lettera dell'alfabeto --> Fifth letter is the sixth letter of the alphabet.
And that's F.

5) This one was a bit unfair. You were supposed to find this by googling "skip cipher". Though it turned that at least one person managed to decipher the message without the help of this site.
VG1oYmVlIHJ0LmggaVdyaGRpIGNsaGUgdHl0b2V1ciAgd2lpc2wgbG4gb2h0YSB2YWUgIGx0ZW90IHRiZXJydSB0YmV1ZnRvIHJhYyBlbi51 --> Tmhbee rt.h iWrhdi clhe tytoeur wiisl ln ohta vae lteot tberru tbeufto rac en.u --> The third letter is not a letter but a number. Which you will have to bruteforce.
Oh, come on, it's just 10 possible version. And you wouldn't have to do it for long anyway since the right number is 1.

So the giveaway code is LT1XF.