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Centers of many galaxies host a dense stellar system called nuclear star cluster with a central massive black hole. Extreme stellar densities make this environment an efficient breeding ground of a variety of astrophysical transients, like tidal disruption events (TDEs) of stars and extreme mass ratio inspirals (EMRIs) of stellar-mass black holes. The upcoming wide field survey instruments like Vera C Rubin Observatory and mHz gravitational wave detectors like LISA and TianQin will revolutionize the field of nuclear transients. These transients offer a unique probe into the dynamical environment of galactic nuclei and demographic properties of astrophysical black holes. The classical channel of weak two-body scatterings among stellar objects is the standard route to exciting the orbital eccentricities of a star/BH leading to plausible formation of a TDE/EMRI. I will present a semi-analytical framework that identifies the underlying self-similar nature of this standard channel of EMRI formation, and improves upon the previous estimates of transient formation rates. Then, I will discuss the non-classical ways to channel these transients in a gas-rich active galactic nucleus (AGN) hosting a massive gas disk, where higher orbital eccentricities can be excited over much shorter secular timescales. I will show that TDE formation rates can be enhanced more efficiently for a time-evolving AGN. These findings are in alignment with the observed preference of TDE hosts for recently-faded AGNs. In the end, I will discuss the impact of traditionally ignored strong scatterings on transient formation. In particular, strong scatterings can suppress EMRI rates in highly dense nuclei upto an order of magnitude, and should be mandatorily incorporated in future detection rate estimates for LISA.