NA guilds:

>Edan
Inner_Circle:   Add Naaki on steam for an invite or whisper Winda, Accelerando, Opaila, Deadbeat.
Aesthetic:      Add DonThyDong on steam or whisper Aoide, Exeona, Bryne, Odet.
YotsubaCorp:    Post in thread with IGN visible
Who:            Who knows?!

>Orwen
Mabinogi:       Whisper the guild leader for invites [character names: Ichidou, Cypria, Kraydor, Irmingard, Yeong_Ja] or add him [family name: Etria].

>Uno
TOPS:          Whisper cloudsky45 to join.
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EU guilds:

>Jordine
PettanCo (/a/ & /v/): for invites whisper Billy/Jachlem or Mikami/Spray/Shoujo