Chess Quiz: You never seen this before

Normally I prefer to analyse my students' games (long time control or rapid) against other players, rather than playing against them myself. But with everyone on the planet playing mainly online blitz or bullet these days, I have to play against my students often. In some of these games, some truly curious position have occurred, or might have occurred! (Hint: Not necessarily simple.)

June 22-27, 2020:

Black to move

(Variation from the game)
White to move

(Variation from the game)
Black to move

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