Invulnerable kuva lich and endless supply of thralls

[Nneevor]

During a lich mobile defense mission on Boethius - Mercury lv1 kuva lich spawned, started casting its abilities and became permanently invulnerable. I could drop its shield, but all three health bars were permanently greyed out, and no futher dmg was applied after shield loss and no parazon prompt ever triggered.

Lich was on first rank, spawned from rhino prime and had rhino's abilities, i was also in the same rhino prime that spawned him.

I was able to successfully complete mission without killing the lich, just stomp-stunning and drawing his attention from the objective, and then extracting as usual.

During that I've noticed that, as long as lich is in mission, kuva thralls continue to spawn (possibly endlessly) and i was able to obtain 2-3 times more requiem murmurs then expected from this mission. This effect seemed to stop only after final objective was marked as completed.

During whole mission lich has triggered several "instakill" animations against my warframe without any visible effect, aside from knockdown, and without rank-up effect or despawning.

Edited November 7, 2019 by Nneevor
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