- "Consuming Zephon’s apostate soul has bestowed on you a new gift. Like his vampire spawn, you are able to scale certain walls which are otherwise impassable - but only in the physical realm. In the spirit world, these insubstantial edifices will not support you."
- ―Elder God — Listen (file info)
Scalable walls, also known as Climbable walls or simply Walls, were an environmental feature first introduced in Legacy of Kain: Soul Reaver and recurring in Soul Reaver 2 and Legacy of Kain: Defiance. Represented by multiple horizontal lines across a surface, scalable walls were initially impassable, however once Raziel defeated Zephon in Soul Reaver he gained the ability to scale them in the Material Realm and from then on he could climb any surface marked with the distinctive pattern. Though Raziel could not initially scale the walls in the Spectral Realm, by the time of Defiance he was able to scale them in both realms.
Scalable walls first appeared in Legacy of Kain: Soul Reaver as specially textured walls consisting of multiple horizontal lines.[Soul Reaver] The first of these walls would be observed as Raziel exited the Underworld in the Legacy of Kain: Soul Reaver prologue[Soul Reaver/1] and they could be seen throughout Nosgoth, despite being initially unusable.[Soul Reaver] Later when Raziel traveled to the Silenced Cathedral in The Silenced Cathedral (chapter), he was able to defeat his brother Zephon and by consuming his soul, gained the Scaling walls ability of the Zephonim vampires.[Soul Reaver][Soul Reaver/7][Soul Reaver/8] Unlike the Zephonim, Raziel was only able to use the ability on the specially textured scalable walls in the Material Realm, allowing him to reach higher areas and access previously blocked locations.[Soul Reaver][Soul Reaver/7][Soul Reaver/8][Soul Reaver manual (UK)][Soul Reaver manual (US)][Soul Reaver strategy guide (Prima)] Initially Raziel was able to climb one of the walls in the Pillars chamber of the Sanctuary of the Clans to climb beyond it and reach the exposed Tomb of the Sarafan;[Soul Reaver][Soul Reaver/9] and he would frequently be called to use them throughout the rest of the game.[Soul Reaver]
Scalable walls returned in Soul Reaver 2, where with Scaling walls now an innate ability, Raziel was able to use scalable walls to climb at any time throughout all three eras of Soul Reaver 2, again allowing Raziel to reach higher levels. As before, Climbing was only available in the Material Realm and would be aborted if Raziel Shifted or was struck by an enemy or projectile, causing Raziel to drop to the floor below.[Soul Reaver 2][Soul Reaver 2 manual][Soul Reaver 2 strategy guide (Prima)]
Scalable walls were again featured in Legacy of Kain: Defiance and as Scaling walls was now a common ability the walls could for the first be used by Kain as well as Raziel. As in previous titles, the walls could be climbed from the beginning simply by jumping towards them, though the process would be aborted if struck. There were several minor changes however, with Raziel now able to use them in the Spectral Realm as well as the Material Realm and both characters could also able kick-jump off the walls to propel themselves away to higher platforms behind them.[Defiance][Defiance manual][Defiance strategy guide]
In the Legacy of Kain: Soul Reaver alphas, climbing walls do not bear the 'ribs' of their final designs, instead featuring plain walls. In at least one area Zephonim webbing seems to have been used as a placeholder or prototype design.
- In Legacy of Kain: Defiance, for the first time Raziel was able to use the scaling walls ability in the Spectral Realm. Although the addition was unexplained in-game, Chris Bruno suggested the improvement was something "Raziel has learned over time". The ability was originally intended to be revealed in cut underworld room Eldergod 5a, but the room and its dialogue were removed. Perhaps connected to Raziel's Spectral climbing, it is noted that certain Scalable walls will now appear in only one realm, forcing Raziel to shift to use them.[Defiance manual]
- Kain demonstrated the ability to climb the same walls as Raziel in Legacy of Kain: Defiance, though it is unknown how he developed this ability.[Defiance] Kain had previously been shown similarly "Climbing Ladders" in Blood Omen 2, but this was counted as an 'Object Interaction' and not as involving a distinct ability. Presumably any humans could have used them, though they are not observed doing so in-game.[Blood Omen 2][Blood Omen 2 manual (US)][Blood Omen 2 manual (UK)]
- Soul Reaver manuals describe the scaleable walls by the texture designs: "Only certain wall types are scaleable. Rough, organic, crumbly or mortared stone walls cannot be climbed."[Soul Reaver manual (UK)] Similarly Soul Reaver 2 manuals describe them as "certain walls which are distinctively etched.",[Soul Reaver 2 manual] whereas Defiance manuals simply mention "a climbable wall surface."[Defiance manual] Prima guides refer to them as "certain material plane surfaces", "special walls", "wall-crawl surfaces", "climbing surfaces", "climbable walls" or simply "walls".[Soul Reaver 2 strategy guide (Prima)][Defiance strategy guide] In some sources, the use of the Scaling Walls ability is also mentioned to specifically involve the use of Claws.[Soul Reaver manual (UK)][Soul Reaver 2 strategy guide (Prima)]