Planetary nebulae in the Magellanic Clouds

We present a large optical and UV sample of PNe in the LMC and SMC used as tracer to improve both, the spatial distribution to obtain a galaxy uniform coverage, the time sampling to cover a wider Initial Abundances domain. This allows to derive their abundances, and gives new hints into the knowledge of the Intermediate Mass Star Evolution and the chemical evolution (Yields) with respect to metallicity changes. We observe the HBB reaction and also Oxygen depletion (massive stars) or Oxygen production (like Carbon) during the 3rd dredge-up (more efficient at lower metallicity). As a consequence the Oxygen can not be used to derive the initial composition of the progenitor star, we have to use other elements like Sulfur or Argon.