  We study generalised rock-paper-scissors models with an arbitrary odd number
N \geq 5 of species, among which n are weak, with 2 \leq n \leq (N-1)/2.
Because of the species' weakness, the probability of individuals conquering
territory in the cyclic spatial game is low. Running stochastic simulations, we
study the role of unevenness in the rock-paper-scissors game in spatial
patterns and population dynamics, considering diverse models where the weak
species are in different positions in the cyclic game order. Studying systems
with five and seven species, we discover that the individuals' spatial
organisation arising from the pattern formation process determines the
stability of the cyclic game with multiple weak species. Our outcomes show that
the presence of species unbalances the spatial distribution of organisms of the
same species bringing consequences on territorial dominance, with the
predominant species being determined by the position in the cyclic game order.
Our simulations elucidate that, in general, the further apart the regions
inhabited by different weak species are, the less the coexistence between the
species is jeopardised. We show that if multiple weak species occupy adjacent
spatial domains, the unevenness in the cyclic game is reinforced, maximising
the chances of biodiversity loss. Our discoveries may also be helpful to
biologists in comprehending systems where weak species unbalance biodiversity
stability.
