public EffectWeightedRandomList add(int weight,@Nonnull IEffect effect){
  effects.add(new WeightedEffect(weight,effect));
  return this;
}

public EffectWeightedRandomList add ( int weight , @ Nonnull IEffect effect ) { effects . add ( new WeightedEffect ( weight , effect ) ) ; return this ; }
adds a new weightedeffect
