'''Editor's Note:''' A fantastic and impressive logo for the time that was sadly wasted, having seemingly only been used on a game installer and not any actual titles.
'''Final Note:''' In 1998, Sierra On-Line split their publishing into five different brands and sub-labels - [[Sierra Attractions]], Sierra Home (which was previously used beforehand), [[Sierra Sports]], [[Sierra FX]] and [[Sierra Studios]]. It wouldn't be until 2001 when all of them (except for Sierra Home) would be under one brand again.
===3rd Logo (as Sierra FX) (July 11-December 7, 1998)===
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{{YouTube|id=lz8OK9xmNX0}}
'''Nicknames:''' "Flying Letters", "The Winged S"
=== 5th3rd Logo (August 21, 2001-October 4, 2002)=== ▼
'''Logo:''' On a black background, a {{color|blue}} light shines as the letters of the previous logo swirl around inside it. As they get closer together, the light brightens before forming a glare. The Sierra FX logo, which is the 1998 Sierra logo with {{color|blue}} spikes and "FX" in a black connected font with a {{color|blue}} glow, appears as a light passes behind it.
'''FX/SFX:''' The fragments flying and shining.
'''Music/Sounds:''' A mystic synth tune with a strange flute when the logo appears.
'''Availability:''' Only seen on 2 [[Yosemite Entertainment]] games, which were ''Police Quest: SWAT 2'' and ''Quest for Glory V''.
'''Editor's Note:''' None.
===4th Logo (as Sierra Studios) (September 30, 1998-June 22, 2001)===
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{{YouTube|id=m4dZtgDBDrs}}
'''Nicknames:''' "Constructed Sierra", "The Winged S II"
'''Logo:''' On a rotating starry background, {{color|blue}} wireframes of the 1998 Sierra logo ("SIERRA" in a strange font with a "wing" on the "S" made from spikes) zoom out and spin into place, along with "STUDIOS". A ring also takes its place surrounding the "S". Then, metal shards cover the logo, turning it {{color|silver}}. The logo (the bar, the "STUDIOS" text and the ring) turns {{color|gold}} and proceeds to shine brightly, ending with the ring giving off a gleam.
'''Variant:''' A short version exists, with the logo closer to the screen and only having the ring shine. It also only has sounds of the ring shining.
'''FX/SFX:''' The logo forming.
'''Music/Sounds:''' A deep synth note and several whooshes, ending with sparkles and a dark bell tune.
'''Availability:''' Uncommon.
*Appears on Sierra published games from the era. The most well-known game with this logo is ''Half-Life''.
*Other games include ''Lords of Magic'', ''Team Fortress Classic'', ''Counter Strike'', ''Ground Control'', ''SWAT 3: Close Quarters Battle'' (Original and Elite Editions only), ''King's Quest: Mask of Eternity'' and ''Homeworld Cataclysm''.
*The shortened version appeared on ''Caesar 3''.
*None of the Steam releases of [[Valve Corporation|Valve]] games from this era will have this logo.
'''Editor's Note:''' None.
▲===5th Logo (August 21, 2001-October 4, 2002)===
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