Start game as usual, then use the following level-codes:

 - Level Set 1

 LEVEL 2 - NEBULU
 LEVEL 3 - ZWARIG
 LEVEL 4 - EGIPET
 LEVEL 5 - TASTER
 LEVEL 6 - ZAPPER
 LEVEL 7 - BUNGALO
 LEVEL 8 - SANDAL
 LEVEL 9 - ONIZIS
 LEVEL 10 - ZANASIS
 LEVEL 11 - XENOLR
 LEVEL 12 - ALIEST
 LEVEL 13 - XFINDER
 LEVEL 14 - TERGINUS
 LEVEL 15 - BAPEDU
 LEVEL 16 - DUNDUL
 LEVEL 17 - GONZOOO
 LEVEL 18 - KINESTET
 LEVEL 19 - ARGON
 LEVEL 20 - NOLOGICK
 LEVEL 21 - UNNEREAL
 LEVEL 22 - OPENWIND
 LEVEL 23 - SKELETAR
 LEVEL 24 - BIGBOSS
 LEVEL 25 - INFERNALIS
 LEVEL 26 - DASTUL
 LEVEL 27 - ANABIOSIS
 LEVEL 28 - BANGALOR
 LEVEL 29 - ISTENRIX
 LEVEL 30 - BLEZUS
 LEVEL 31 - KUINSI
 LEVEL 32 - DARUTA
 LEVEL 33 - UNIONIS
 LEVEL 34 - DESTRIST
 LEVEL 35 - WERTIKS
 LEVEL 36 - LANDER
 LEVEL 37 - GASETER
 LEVEL 38 - DUQSTUN
 LEVEL 39 - BABURIS
 LEVEL 40 - GLAASER
 LEVEL 41 - GILBOBLAST
 LEVEL 42 - BALLASTER
 LEVEL 43 - CENTRUN
 LEVEL 44 - NIKOLIS
 LEVEL 45 - ZERKONIY
 LEVEL 46 - SANDRAGORIS
 LEVEL 47 - SIGERUS
 LEVEL 48 - SLUTONIS
 LEVEL 49 - LEOPARDER
 LEVEL 50 - FINALTICS

 - Level Set 2

 BASTUS     - 02
 STARTREST  - 03
 IKLEX      - 04
 XENON      - 05
 VAMPUS     - 06
 NUBUK      - 07
 IBURIS     - 08
 CERBER     - 09
 VIMBELDAN  - 10
 TIBIC      - 11
 MAJICK     - 12
 FEBBI      - 13
 XIKEBY     - 14
 NMIHY      - 15
 HYBHY      - 16
 KCBVCCC    - 17
 GEBIXIX    - 18
 MKCBI      - 19
 BCCKEOG    - 20
 YBBIIM     - 21
 CIBER      - 22
 LIGXIM     - 23
 NEKNC      - 24
 EBIJBM     - 25
 HMIXY      - 26
 MBNECEL    - 27
 NMIKIB     - 28
 EXIBET     - 29
 BASIS      - 30
 GIEBLE     - 31
 HYMIX      - 32
 YBECBELL   - 33
 HIXEX      - 34
 IXEGL      - 35
 MBHI       - 36
 KMIXI      - 37
 HYXYB      - 38
 MNYEL      - 39
 KMMII      - 40
 KENCEN     - 41
 MMXI       - 42
 OIXBIX     - 43
 BEGCEL     - 44
 VIGCEBEU   - 45
 MBIXEL     - 46
 EKIYL      - 47
 YXCEBEL    - 48
 BIMIXI     - 49
 QUITER     - 50

 - Level Set 3

 ZMM        - 02
 MAMZ       - 03
 ARAS       - 04
 FAPIR      - 05
 NGZM       - 06
 MELE       - 07
 ARMZ       - 08
 FMM        - 09
 FMZZ       - 10
 XX         - 11
 DMFM       - 12
 MAAA       - 13
 EAFLMZ     - 14
 BADA       - 15
 YA         - 16
 FINIT      - 17
 APAX       - 18
 GZM        - 19
 MZNU       - 20
 AYZIS      - 21
 PADAP      - 22
 VALID      - 23
 AGA        - 24
 SFIR       - 25
 PAF        - 26
 AFIN       - 27
 DATA       - 28
 YGSA       - 29
 FAPPM      - 30
 GINA       - 31
 AFAF       - 32
 EAFCA      - 33
 NFIL       - 34
 AFMZ       - 35
 GCAFG      - 36
 DAZA       - 37
 EDF        - 38
 MDRIZ      - 39
 SAFER      - 40
 YANA       - 41
 UNIX       - 42
 UNAS       - 43
 ALLA       - 44
 ALBINELLA  - 45
 LIMZA      - 46
 ZMDE       - 47
 AMZIR      - 48
 NAFDCGE    - 49
 SXGFG      - 50

 - Christmas Levels

 TREBCE     - 02
 EGISTER    - 03
 IZISM      - 04
 NISYX      - 05
 FOREST     - 06
 TCCCCC     - 07
 IZER       - 08
 NEYE       - 09
 MERRY      - 10
 HAPPY      - 11
 LENTER     - 12
 GETIT      - 13
 NIKZ       - 14
 MINDER     - 15
 JULITU     - 16
 QSTINN     - 17
 HUNT       - 18
 TIXIC      - 19
 BOREY      - 20
 TASER      - 21
 IQURIS     - 22
 XILIX      - 23
 STILUS     - 24
 INVOI      - 25
 BASMAN     - 26
 XINAS      - 27
 SINTUSB    - 28
 LIVI       - 29
 OOSTIS     - 30
 BANIX      - 31
 OTSUTSI    - 32
 INHSIN     - 33
 MINKI      - 34
 VASIX      - 35
 INTER      - 36
 OKINOT     - 37
 LABIRIS    - 38
 MALVIN     - 39
 VAVEL      - 40
 YTNHOT     - 41
 TSQUVSI    - 42
 HQUTSC     - 43
 HAUTSI     - 44
 ISHOI      - 45
 IVONUTSI   - 46
 DEEPFOREST - 47
 RELGAM     - 48
 BIGSTER    - 49
 FINLAKEM   - 50

 - In Spring Levels

 HNYY       - 02
 YUOHYN     - 03
 UFOUG      - 04
 RUOED      - 05
 ZSNYOH     - 06
 HIIII      - 07
 UFYN       - 08
 RYEY       - 09
 QYNNE      - 10
 TLLE       - 11
 PYRYN      - 12
 YHUH       - 13
 QURXYN     - 14
 VIPUHI     - 15
 MOHURR     - 16
 TIHR       - 17
 HUDUL      - 18
 SNYE       - 19
 HOYN       - 20
 UMINO      - 21
 DUPUD      - 22
 OHUPIO     - 23
 URJISU     - 24
 OGRE       - 25
 DURO       - 26
 OURIHO     - 27
 PUJU       - 28
 MSOHUO     - 29
 RUDDY      - 30
 SHOIHOU    - 31
 URTOUR     - 32
 QURWU      - 33
 ZERO       - 34
 URHYN      - 35
 SWURSH     - 36
 PUNOU      - 37
 QPIR       - 38
 JJYP       - 39
 EHRTSH     - 40
 HOMIJOU    - 41
 TMIHOL     - 42
 TIHOU      - 43
 UOTSU      - 44
 UJSROU     - 45
 XYLZIXNOU  - 46
 NYPQ       - 47
 UOHYN      - 48
 ZURPWSQ    - 49
 GLAASERS   - 50

 - Abstract Levels

 VPGG       - 02
 GKQVGP     - 03
 KXQKY      - 04
 LKQ2       - 05
 DMPGQV     - 06
 GOWW       - 07
 KXGP       - 08
 LGG        - 09
 OGPP       - 10
 JRR        - 11
 NGLGP      - 12
 GVKV       - 13
 OKLFGP     - 14
 HWNKVW     - 15
 SQVK       - 16
 JWVL       - 17
 VKZKR      - 18
 MPG        - 19
 VQGP       - 20
 KSWPQ      - 21
 ZKNKZ      - 22
 QVKNWQ     - 23
 KLTWMK     - 24
 QYL        - 25
 ZKLQ       - 26
 QKLWVQ     - 27
 NKTK       - 28
 SMQVKQ     - 29
 LKZZG      - 30
 MVQWVQK    - 31
 KLJQKL     - 32
 OKLIK      - 33
 DLQ        - 34
 KLVGP      - 35
 MIKLMV     - 36
 NKPQK      - 37
 ONWL       - 38
 TTGN       - 39
 VLJMV      - 40
 VQSWTQK    - 41
 JSWVQR     - 42
 JWVQK      - 43
 KQJMK      - 44
 KTMLQK     - 45
 FGRDWFPQK  - 46
 PGNO       - 47
 KQVGP      - 48
 DKLNIMO    - 49
 YRMLM      - 50