Online Services and MMORPGs I have Played, this list is non-exhaustive, and may be updated without notice. All of the Online Services were likely played with their original/first publisher. Such as Aeria Games for Eden Eternal/Grand Fantasia. These will be usually marked, but if they aren't marked, it likely means that they only had one publisher, or I can't remember the publisher's name.

§ at the end of a list item indicate they are one of my favorites.
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Active Worlds (About an Hour, mostly in AWEDU)
Adventure Quest Worlds (Post-Death)
AIKA
Aion
Allods
Angels Online
Anthem
ArcheAge
Asda Story / 2
Astellia
Aura Kingdom (Aeria ver.)
Bitcraft
Black Desert Online
Black Gold Online
Blade & Soul
BLESS
Boundless
CABAL
City of Steam: Arkadia
Closers
Continent of the Ninth Seal (C9)
Deadlock (Tutorial/Sandbox Only - Didn't like the skills/mechanics)
Defense of The Ancients 2 (DOTA 2) (One Match)
Defiance
Destiny / 2
Digimon Masters (Tutorial Only)
Dofus
Dragon Nest
Dream of Mirror Online
Dungeon Fighter Online (2D Ver.)
Echo of Soul
Eden Eternal (Aeria ver.)
Elite:Dangerous
Elsword
Ether Saga Odyssey/Online
Fiesta Online
Final Fantasy XI
Final Fantasy XIV §
Firefall
FlyFF (pre-Gold)
EverQuest 2 (An hour or two.)
Forsaken World
GIGANTIC (the MOBA) (One Match)
Granado Espada
Grand Fantasia (Aeria ver.)
Guild Wars 2
Holy Beast Online
Hypixel Skyblock (Minecraft)
Iris Online
Kitsu Saga (Aeria ver.)
LaTale (OGPlanet, pre-Steam)
League of Legends (2 Matches)
Lime Odyssey (Never released, alpha only) (Aeria ver.)
Lost Ark
Lucent Heart
Luminary Online
Mabinogi
Maple Story
Maple Story 2
Neverwinter Online (Perfect World Entertainment)
New World
NosTale
Old School RuneScape (After they named it such, During RuneScape 3/HTML5)
Onigiri Online
Palia
Path of Exile
Perfect World International
Phantasy Star Online 2 / NGS §
Ragnarok Online
Ragnarok Online 2
Remnant Knights
Requiem
Revelation Online (Tutorial / First Area Only)
RIFT
RuneScape (Pre-Tutorial Island Implementation, 5 Minutes Only)
Runes of Magic (pre-Steam, pre-GameForge)
Second Life (10-20 Minutes)
Secret Worlds (Pre-Legends and Legends)
Skyforge
SMITE (Three Matches)
Soulworker
Star Citizen (Persistent Universe)
Star Wars: The Old Republic (Trooper, Initial Two Zones)
Swords of Legends
TERA (EnMasse / pre-Steam)
The Elder Scrolls Online
The Secret World (Pre-Legends)
Throne and Liberty
Toram Online
Tower of Fantasy (Tutorial/Prologue Only)
Tree of Savior §
Trickster Online §
Trove
Vindictus (aka Mabinogi Heroes)
Wakfu
Warframe
WildStar §
Wonderland Online
World of Kung Fu
World of Warcraft
Wynncraft (Minecraft)

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