In this paper, we intend to describe and discuss the grammatical status of the V1-V2 (Cy/vy) constructions found in Mbya Guarani which can express simultaneous events, among other meanings, and which involve a single clause. We suggest here that this verbal complex can be treated as a case of asymmetrical verbal serialization because it contains verbs from a major lexical class, occupying the V1 slot, followed by a more restricted intransitive verbal class, such as movement, postural, or stative verbs, which stands in the V2 position. The curious property of these constructions is that V2 can be transitivized through the attachment of applicative or causative morphemes and “share” its object with transitive V1. “Object sharing” is another property attributed to serialization, as suggested by Baker and Baker and Stewart, which may be seen as a strong argument in favor of the present hypothesis. We will also provide evidence to distinguish Mbya Guarani V1-V2 (Cy/vy) complex from other constructions, such as temporal and purpose subordinate clauses, involving the particle vy.