We successfully achieved a unique system in which nonemissive tetrazine molecules become even darker, and emissive pyridazine molecules become even brighter in aggregate states. Encouraged by this result, we calculated the emission enhancement ratio upon click reaction (IAC/IBC) in the aggregate state to verify the impact of this aggregationformation strategy on the emission enhancement ratio. The PR-Tz negative control demonstrated a very weak IAC/IBC around 20 in an aqueous environment due to the strong ACQ effect in water (Figure ). In contrast, TPE-Tz, possessing the most canonical AIEgen unit, displayed a significantly high emission enhancement ratio of IAC/IBC up to 4833 (Figure ). Even TPA derivatives, which act as less active AIE units, resulted in a high emission enhancement ratio upon click reaction (Figure , Supporting Information), as evidenced by MTPA-Tz (IAC/IBC = 2439) and MBTPA-Tz (IAC/IBC = 209). Only TPA-Tz did not exhibit strong turn-on emission (IAC/IBC = 93) among AIE-Tz, as the post-click reaction compound was still affected by n-π* type quenching from the pyridazine group and did not exhibit a strong emission (quantum yields < 0.01, Table and Figure in Supporting Information). Multiple reports suggest a negative correlation between emission wavelengths and emission enhancement ratios for tetrazine fluorogenic probes. To confirm this, we plotted IAC/IBC values of previously reported tetrazine dyes against their emission wavelength. As a result, the plotted data points revealed a distinct and consistent trend, illustrating that as the emission wavelength increased, the emission enhancement ratio decreased. This visualization successfully substantiated the negative correlation between these two parameters. Most importantly, we observed that AIE-Tz demonstrated a very strong turn-on property compared to previously reported molecules in each emission wavelength. Notably, the 4833-fold emission enhancement of TPE-Tz is one of the best values among previous reports (Figure and Table in Supporting Information). In conclusion, we discovered that connecting AIEgens to tetrazine units is an effective and general strategy for achieving strong fluorogenic signals in aqueous systems that inevitably cause aggregation of hydrophobic molecules.