Good Riddles

Question: 1 11 21 1211 111221 312211 13112221 1113213211 what comes next?

Question: I work in a battle of wits. The battle is again with only two while an army each has. Each must take a turn in stratagem but to win the leader must die. What am I?

Question: How do you drown a hipster?

Question: What kind of math do Owls like?

Question: I am taken from a mine, and shut up in a wooden case, from which I am never released, and yet I am used by almost everybody.

What am I?