HashMap<String, Integer> hits = new HashMap<String, Integer>();

    // Player causing damage, attacking another entity
    private void onPlayerAttack(Player attacker, ItemStack weapon, Entity entity, EntityDamageByEntityEvent event) {
        hits.put(attacker.getName(), hits.get(attacker.getName()) + 1);
        if (weapon != null) {
            if (isAxe(weapon.getType())) {

            }

            if (isSword(weapon.getType())) {
                // Sword + Aqua Affinity = Slowness
                if (hasEnch(weapon, AQUA_AFFINITY, attacker)) {
                    if (entity instanceof LivingEntity) {
                        ((LivingEntity) entity).addPotionEffect(new PotionEffect(PotionEffectType.SLOW, getLevel(weapon, AQUA_AFFINITY) * 20, 0));
                    }
                }
                // Sword + Bane of Arthropods = Poison one second per level
                if(hasEnch(weapon, BANE_OF_ARTHROPODS, attacker)){
                    if(entity instanceof LivingEntity){
                        ((LivingEntity)entity).addPotionEffect(new PotionEffect(PotionEffectType.POISON, getLevel(weapon, BANE_OF_ARTHROPODS) * 20, 0));
                    }
                }
                // Sword + Infinity = heals 1/4 of the damage you did to the enemy every 3rd hit.
                if(hasEnch(weapon, INFINITY, attacker)){
                    if(hits.get(attacker.getName()) % 3 == 0)
                    {
                        attacker.setHealth(attacker.getHealth() + (event.getDamage() / 4));
                    }

                }
            }
        }