What does てmean in this sentence?
After trying to learn Japanese with textbooks I decided to try and learn it the way I learned English - playing games.

Now, I have this sentence:

一つの国家を瞬く間に滅ぼし、魔族を束ねて勢力を拡大、周辺国家を震え上がらせた。

I know some basic grammar and understand the general meaning, but don't know what て means in 魔族を束ねて勢力を拡大.

Can anyone explain me the grammatical meaning of て　in this sentence? Does it connect 束ね and 勢力, or does it modify 束ね? In what way?

Question

What does てmean in this sentence?
After trying to learn Japanese with textbooks I decided to try and learn it the way I learned English - playing games.

Now, I have this sentence:

一つの国家を瞬く間に滅ぼし、魔族を束ねて勢力を拡大、周辺国家を震え上がらせた。

I know some basic grammar and understand the general meaning, but don't know what て means in 魔族を束ねて勢力を拡大.

Can anyone explain me the grammatical meaning of て　in this sentence? Does it connect 束ね and 勢力, or does it modify 束ね? In what way?

Answer

It's a marker of the joining form of Japanese verbs.
Basically it connects two verbs together and suggests the sequence of actions.
V1てV2 shows that V2 happens after V1, though sometimes it's just a connector of verbs that does not emphasize which action occurs first, like "and" in English.
Hope this helps! :)
P.S.
I wonder how you would be able to understand Japanese texts without understand what て stands for.