That isn't a bug. In Terraria there are two types of damage: direct and piercing.
Direct attacks are from non-piercing weapons (crystal storm spell, any gun using musket balls, razorpine, Pygmy staff, etc) and can do up to a very large amount of hits per second, as theoretically they can hit a target an infinite amount of times per second, provided it hits fast enough
Piercing attacks are from piercing weapons (spears, guns with crystal bullets, golden shower spell, and the spider staff as examples) are limited to inflicting 6 attacks per second, for balancing reasons. Between each attack from a piercing weapon, the enemy is made invincible for ~1/6th of a second.
With the spider staff, the spiders latch on to enemies, never letting go till the opponent dies, or the summoner. This means that the spider does damage to the enemy as soon as its frame of invincibility ends, putting it straight back into the invincibility stage.
The venom inclicted by the spider is a debuff, and should not affect your ability to damage an enemy as it is a different thing entirely
What this means:
- spiders will do a lot of damage per second against a single target when attached
- Additional spiders won't do additional damage against a single target
- Your attacks will not register against a target being harassed by a spider because the enemy is momentarily invincible
- Venom debuff doesn't affect your ability to hit a target, but it raises (slightly) the spiders DPS against a single target
Hope it helps!
The heart reach potion is broken across all console versions (unknown about Nintendo versions because that's based on mobile)
It's also hard to screenshot because the hearts are usually put in the floor, & in the Vita's case, the screens too small to see where they went.
In any case I'll try to post a screenshot, or gif, of the bug in effect
The pirate staff is also broken? IS NO MINION SAFE ANYMORE?! Please tell me the tempest staff works as intended, because I don't want my summoner run to end prematurely..
