The study of top quark is one of the major program at LHC. Essentially being a top factory, LHC provides a unique opportunity to study multi-top productions. In the Standard Model (SM), the single-top, $t \bar t$ and four-top production cross sections are very large and well over pb level, while the triple-top is few fb. Any enhancement in triple-top production would be intriguing. This may be realized in the Two-Higgs-Doublet-Model (2HDM) without a discrete $Z_2$ symmetry, where both the doublets couple to the up- and down-type quarks. After diagonalization of the fermion mass matrices, two different Yukawas $\kappa_{f}$ and $\rho_{f}$ emerge, where $\kappa_{f}$ is diagonal and real, however, $\rho_{f}$ is in general non-diagonal and complex. Extra Yukawas $\rho_{tt}$ and $\rho_{tc}$ with $\mathcal{O}(1)$ magnitude can enhance the cross section of triple-top process to pb level. In this proceeding we discuss the discovery potential of new scalars via two novel signatures: $cg\to t H^0/ tA^0\to t t \bar c$ (same-sign top) and $cg\to t H^0/ tA^0\to t t \bar t$ (triple-top) at LHC. Discovery may shed light on the Baryon Asymmetry of the Universe.