The Amplified Force Projectile was an ability that Raziel was intended to gain in the original version of Legacy of Kain: Soul Reaver . An upgrade of the Telekinetic force projectile, Raziel was to have gained the ability after the defeat of his brother Turel. With the removal of Turel (and many other elements of this version of the storyline), the ability was removed and Raziel's telekinetic abilities were not upgraded until he gained Enhanced telekinesis in Legacy of Kain: Defiance.
Little is known about the removed Amplified Force Projectile, apart from quotes from developers prior to Soul Reaver's release, indicating that it's projectile would have "pushed enemies further...reduced them to a stunned state" and would have broken more substantial objects. Raziel was to have gained the ability later on in the original Soul Reaver Storyline, after he travelled to Turel's Clan Territory to confront his brother Turel. Much like confrontations with his other brothers, Turel's defeat would have allowed Raziel to consume his Soul and gain a 'watered-down' version of the clan's major abilities, In this case gaining a version of the Turelim's telekinetic abilites that enhanced the Telekinetic force projectile Raziel had previously gained from the Tomb Guardian and the telekinetic force projectile relic.
Within Soul Reaver's game code, the original dialogue for the Turel battle is still present, but there is no mention of Raziel gaining the Amplified Force Projectile, additionally there is an alternate effect for the Telekinetic Force Projectile that can be accessed in-game, but this has less 'ripples' than seen in the Telekinetic Force Projectile and isn't as striking - it may be that the effects for the two abilities were swapped when the Amplified Force Projectile was removed.
The evolved Turel finally returns in Defiance. By this stage Raziel's telekinetic ability is referred to as telekinesis, but in a similar vein to the Telekinetic/Amplified Force Projectile upgrade, TK (Telekinesis) is upgraded by Turel's death (and Raziel's consumption of his Soul ) into the Enhanced telekinesis ability, which finally made Raziel's TK comparable to Kain's, enabling Raziel to telekinetically throw enemies.
The Amplified Force Projectile ability is part of a long line of 'Telekinetic ' abilites seen in the Legacy of Kain series. Blood Omen featured several abilities that involved firing projectiles of a magical nature, most notably Energy Bolt. Soul Reaver (and Soul Reaver 2 ) featured the related Telekinetic force projectile and Reaver bolts (both to originally to have been upgraded to the Amplified Force Projectile.) Blood Omen 2 featured Kain gaining the Dark Gift Telekinesis from the Seer; this ability included a function to manipulate objects with telekinesis. Ultimately the various 'telekinetic' abilities of Raziel and Kain would be united in Defiance under the title of TK, though with notable differences between the versions used by Raziel and Kain, these would later be 'evened out' by Raziel's gaining Enhanced telekinesis from Turel (a slightly different version of the Amplified Force Projectile). The TK (Telekinesis) abilities are likely developed from the Telekinetic Force Projectile and Telekinesis respectively.