// Cumulative upkeep {G}
this.addAbility(new CumulativeUpkeepAbility(new ManaCostsImpl("{G}")));
// {2}{G}, Pay 3 life for each velocity counter on Tornado: Destroy target permanent and put a velocity counter on Tornado. Activate this ability only once each turn.
Ability ability = new LimitedTimesPerTurnActivatedAbility(Zone.BATTLEFIELD, new DestroyTargetEffect(), new ManaCostsImpl("{2}{G}"));
DynamicValue lifeToPayAmount = new MultipliedValue(new CountersCount(CounterType.VELOCITY), 3);
ability.addCost(new PayLifeCost(lifeToPayAmount, "3 life for each velocity counter on {source}"));
ability.addTarget(new TargetPermanent());
Effect effect = new AddCountersSourceEffect(CounterType.VELOCITY.createInstance());
effect.setText("and put a velocity counter on {source}");
ability.addEffect(effect);
this.addAbility(ability);