// Equipped creature has defender and "{2}, {T}: Other creatures you control gain trample and get +X/+X until end of turn, where X is this creature's power."
Ability ability = new SimpleStaticAbility(Zone.BATTLEFIELD, new GainAbilityAttachedEffect(DefenderAbility.getInstance(), AttachmentType.EQUIPMENT));
Effect effect = new GainAbilityControlledEffect(TrampleAbility.getInstance(), Duration.EndOfTurn, new FilterCreaturePermanent(), true);
effect.setText("Other creatures you control gain trample");
Ability gainedAbility = new SimpleActivatedAbility(Zone.BATTLEFIELD, effect, new GenericManaCost(2));
DynamicValue xValue = new SourcePermanentPowerCount();
effect = new BoostControlledEffect(xValue, xValue, Duration.EndOfTurn, new FilterCreaturePermanent(), true, true);
effect.setText("and get +X/+X until end of turn, where X is this creature's power");
gainedAbility.addEffect(effect);
gainedAbility.addCost(new TapSourceCost());
effect = new GainAbilityAttachedEffect(gainedAbility, AttachmentType.EQUIPMENT);