Operational State Complexity Revisited: the Contribution of Monsters and Modifiers -- Hypercubes and Isometric Words based on Swap and Mismatch Distance -- Defying Gravity and Gadget Numerosity: The Complexity of the Hanano Puzzle -- Existential and Universal Width of Alternating Finite Automata -- On Jaffe's Pumping Lemma, Revisited -- Operational Complexity: NFA-to-DFA Trade-Off -- The Word Problem for Finitary Automaton Groups -- Separating Words Problem over Groups -- Complexity of Exclusive Nondeterministic Finite Automata -- Shortest Accepted Strings for Two-Way Finite Automata: Approaching the Lower Bound -- Pushdown and One-Counter Automata: Constant and Non-Constant Memory Usage -- Construction of a Bi-Infinite Power Free Word with a Given Factor and a Non-Recurrent Letter -- Merging two Hierarchies of External Contextual Grammars with Subregular Selection -- A Tight Upper Bound on the Length of Maximal Bordered Box Repetition-Free Words.