  Attack-Defence Trees (ADTs) are well-suited to assess possible attacks to
systems and the efficiency of counter-measures. In this paper, we first enrich
the available constructs with reactive patterns that cover further security
scenarios, and equip all constructs with attributes such as time and cost to
allow quantitative analyses. Then, ADTs are modelled as (an extension of)
Asynchronous Multi-Agents Systems--EAMAS. The ADT-EAMAS transformation is
performed in a systematic manner that ensures correctness. The transformation
allows us to quantify the impact of different agents configurations on metrics
such as attack time. Using EAMAS also permits parametric verification: we
derive constraints for property satisfaction. Our approach is exercised on
several case studies using the Uppaal and IMITATOR tools.
