In Solluxbot's timeline, Vriska manipulated Aradia into collapsing Sollux's hive, thus killing him. In essence they completely switched places; Aradia still uncovered the ruins and sent Sollux what he needed to create their version of SGRUB, though Sollux was the one who was dead and Aradia was alive. In this alternate timeline, Sollux was pulling the strings, being the Mage of Doom and attempting to bring them all closer to the ultimate and inevitable fate-- a Twin Armageddon.  He eventually pieced the code together, distributed it, and self prototyped.

Eventually, in an attempt to win back Aradia's favor, Vriska bribed Equius into creating a robotic body for Sollux. This would be the Sollux the ask blog is focused on, and the one you all send your asks to!

The story then continues, with Solluxbot eventually exploding, and then Sollux reaching God Tier. Because Sollux reaches God Tier, however, he uses his doom abilities to fix the fate of the game; they already experienced their first "armageddon" of sorts when SGRUB destroyed Alternia, and with his abilities, he ensured there was no chance of winning. Lord English eventually came along and obliterated their timeline's universe, resulting in the second "armageddon" and fulfilling Sollux's role as the Mage of Doom. 

However, you all are sending asks to the Sollux right in the middle of that timeline, as Solluxbot! Hope that helps explain some things and maybe makes his character seem a bit clearer!