Solar Pillar

The Solar Pillar is one of the four Celestial Towers that appear during the Lunar Events. It is found in the orange/red moon area. Many of the enemies that spawn near it are melee-themed. After defeating the pillar, it drops around 30-49 Solar Fragments on average. As it has melee-themed enemies it drops fragments used to create the endgame melee armor and weapons.

During the battle the pillar will start with a large force field around it, which can be taken down by slaying 100 minions (150 in Expert Mode). Once the field is down, the pillar will become vulnerable, but minions will continue to spawn. The boss itself is fairly easy, having only 20000 HP and you take no damage when touching the pillar melee. However it will occassionally shoot out meteorites that deal around 90 damage per hit. While the boss may not be a threat, the minions it spawns deal high amounts of damage and can easily swarm the player if not taken care of.

Summons:

Tips

 * A quick and effective way to kill all of the pillars is to use the North Pole directly and vertically above a pillar. Even if a player does not have any melee modifiers, if all of the snowflakes can make contact, the pillar should fall in less than 20 seconds.
 * Another strategy is to use the Nimbus Rod as you can leave the place and let it deal damage, placing 2 clouds, you just need to resummon it once, or even none at all.
 * While fighting the Solar Pillar enemies, it is highly recommended to stay grounded. Airborne players are easy prey for the Crawltipede minions, who do an excessive amount of damage.
 * If you have already problems killing the enemies to get the shield down, a good and easy way is to dig a tunnel under the Pillar and use weapons that go through walls like the Death Scythe or the Nettle Burst. It will help a lot using the spore sac (Plantera Expert Item) and a random minion. You can also kill the Pillar using your wall piercing weapon. If it's stuck on a hill, you can build a non-platform bridge to it without being assaulted by Crawltipedes.
 * As with any other pillar, repetitively throwing Vampire Knives will keep you healed most of the time, and if you get to less than 150 hp, use a Greater Healing Potion or higher. This will slowly take out the enemies and the pillar itself. Switching to another weapon is a bad idea, unless you have full Spectre Armor with a hood, though following this strategy, you should have Beetle Armor.

Trivia

 * This pillar seems to have Ebonstone Block, like the other Celestial Towers.
 * This pillar was shown for a few seconds in the trailer for 1.3.
 * Just like the other pillars, you take no damage when touching the pillar melee.
 * Despite dealing no melee damage, this pillar is special in that it shoots out meteorites that deal significant damage.