Terraria (Wiki): Tentacle Spike

The Tentacle Spike is a melee weapon that pierces enemies.

The Tentacle Spike, like the Daybreak, embeds the projectile of the same name into an enemy upon impact and deals +3ATK/s with each strike. These spikes have a 9s duration and can stack up to 5x on each target, dealing +15ATK/s when all spikes are embedded. A Tentacle Spike cannot autoswing. Its attack reaches four tiles in radius. At an optimal distance, the Tentacle Spike can pierce two enemies. However, multiple bodies will be damaged should they all line up for the player.

When normally used, the Tentacle Spike will not emit light, and attacks do not go through walls. It inflicts debuffs on enemies that cause damage to be dealt with gradually.

Combat-wise, the Tentacle Spike's damage output and fast use time make it effective for fighting waves of enemies. All Flask items will imbue their unique effects since the Tentacle Spike is a melee weapon.

The Tentacle Spike is best modified with Legendary for overall stats improvement.