Help with insectoid-bane ranger features

[~Mozza]

Hi guys, me and my DM wanted to add some flavor characters for this guild my PC is in.

My PC is a warlock in this guild/cult devoted to Ragnaros the Firelord, and for those who don't know, he is a boss in World of Warcraft, and one of ours beloved card in Hearthstone.

So, we was talking about adding some flavor and adjusting some aspect of this cult, and I suggested that I can create this ranger character with favored enemy: insectoid, to match the famous quote from Ragnaros "DIE, INSECT!".

I was wondering if there were a prc like the dragonslayer or the abolisher, but where insectoid are the "favored" favore enemy. Also, a killer of insect swarm can be useful too.

In case there is no prc like this, can you suggest some changes to prc already existing or some feats, spells, magic items that even a basic ranger can take to be a "insect-bane".

Thanks in advance.

[ComaVision]

Insects are Vermin type in D&D. You can just take Favored Enemy (Vermin).

[~Mozza]

Insects are Vermin type in D&D. You can just take Favored Enemy (Vermin).

Yeah, I know. I was asking something more like dragonslayer, like, verminslayer.

Or something like nasty arrows that explode and do serious damage to swarms or some stupid combination of arrows and alchemic items that can be thrown into groups of insects.

Also, is there a manual (or manuals) that discusses vermins in depht?