A nuclear spectroscopy experiment was conducted to study a-decay chains stemming from isotopes of flerovium (clement Z = 114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum fiir Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions 48(Ca) + 242(pu) and 48(Ca) + 244(Pu) provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to H-286 and (288)Fl, respectively. A prompt coincidence between a 9.60(1)-MeV alpha particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely 282 Cn. Spectroscopy of 288 F1 decay chains fixed Q(alpha) = 10.06(1) MeV. In one case, a Q(alpha) = 9.46(1)-MeV decay from 284 01 into 280 Ds was observed, with (280)Ds fissioning after only 518 its. The impact of these findings, aggregated with existing data on decay chains of (286,288)Fl, on the size of an anticipated shell gap at proton number Z = 114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.