They were able to revive Taniks because he’s a cyborg that’s more machine than Fallen, which is the main reason why he was always able to come back after being “killed.” He’s really hard to kill. Even after we really stuck it to him on the Moon, SIVA and the Crypt were still able to revive him. He refuses to die, clinging to life in his mechanical corpse. Solkis, on the other hand, was not a cyborg and is straight up dead. On top of that, Eramis wanted to kill Solkis. She would never revive him if given the chance. Furthermore (yeah, the list just keeps going) Taniks was one of the deadliest Fallen that ever lived, even confident that he could kill Draksis (who was historically the deadliest Kell). So Solkis was probably not as deadly as Taniks. And -this is the last one, I promise- Taniks fought alongside Eramis at Twilight Gap and had a strong respect for her, making him a great choice to revive.

Taniks, the Unkillable, Kell of house Zombies. Next raid he returns as a scorn Raid boss in Tangled Shore...

She was not fanatical of House Devils. They were dead to her as soon as she heard the call of the Darkness. She had no house but House Salvation. Just like Taniks. Taniks had no House. So it only makes the MOST sense she would try and recruit him into House Salvation.

I'd have preferred they brought back Aksis frankly but since Luke Smith is on a Rise-of-Iron Retconning spree with D2 it would have never happened. Even Taniks in Deepstone in his final form was very reminiscent of Aksis right down to lengthening the DPS phase with extra work. Problem is that Deepstone is probably the easiest Raid to date, so the "extra work" in the encounters actually just makes it even easier. Rise of Iron also dumped heavily reskinned Fallen with different elements, weapon behavior, and sound design into the game. While Beyond Light is literally just the same Fallen with an old Raid boss becoming a casual "cakewalk" enemy that isn't threatening in the slightest. I hear the "super-powered" one in a patrol zone across the area on Europa and I go out of my way to kill it in 5 seconds for Europa gear rolls. They also added 1 unit (Wyvern) to the Vex roster after having teased that we were fighting construction workers and not warriors the whole time... but that went absolutely nowhere. Neither the characters or game even acknowledges their existence and the new Vex strike is just a big hydra that tries to gatekeep your DPS because Non-Raid bosses aren't allowed to have HP. I'm very split on this DLC. Some good content but also alot of pointless reskins. Them pointlessly reskinning Taniks for the 3rd time only made me lose the honeymoon phase of finally experiencing ""new"" content.

What's a skolis?

They could have brought back skolas or aksis but nooooo let’s bring back taniks and turn him into a fallen centaur