There, i've done some changes in the timeline.

The Battle of Hymns was against Vogani in their homelands.
The siege of Krypola was against a massive slave rebellion.
The battle of shrooms are against a group of elves who thought they could leave the empire. The fools. (Like it was before.)

Claus probably know of the Sa yuta and Avem.
He has fought against the Vogani and been around Mao so he knows those very well, as well as elves.
However the Fu are probably unknown to him.

As for the forsaken, i think t̼̺̞̱̦̞̣̜͕̦͕̳̪͟͢͠h̘͍̯͉͕͠é̶̢̧̬̳͓͙̠̰͔̗̰͘ ̵̛̟̩̮̫̀͜f̶̸̡̛̞̤̲̼̲̗͚̟̲̗̝͕̪̣ǫ̺̣̥̺̲̼̬̩̼̫̤͚̝̜̬̯͢͞ṛ̵̷̞̰̱̲̹͚͇̞̮̝̩̬̱͇͘͢͝s̡̘͈̖͉͢͝a̴̢͓͚͉̘͕̳̜̝̦͙̱̣̮͚̤͍ͅk̀҉̺͈͚͓̝̖͚̩̝̲͉̼̖̱͔̰̺è̴̙̼̘̱̘̞̭͔͜ͅń̴҉̖͚̣̯̳͠ ͚͔̟̦͚̝̮͓͡͡ḁ̸̛̳̖̣͉̠̪̤̗̜͟͡r͜҉̭͓̲̗͚͉̦͈̺͕̯e̸̸̷̩̹͍͍͎̣͕̲̼̘͠ ̶҉͔̼̬̩ą̷̭̲̙̱̟͍̙͠n̸̵̡̬͚̱͔̞͇̗͢ ̙̺̥̯̗̥͈̩̳͙̭̕į̶̴̧̦͖̱̜̣̮͠ǹ̦͉̣̖̟̝̩͝t͡͏͖̝̟̹̱̻̥̮̖̥̬͎͉̻̖͙͇͚ȩ̀̀͏̤̼͖̭͍̖͓̘̫̹̖̻̪̯͕̳͡r̷̢̜̗̲̘͈̦̖̣̣ę̸̫̱̯͍̙̖͚͚̟̖̯̗̮͉̦̼ş̵̷̣̼̮̞͞t̫̙͓̤͙̖̗̙̦̥̰̣̦̦̤̀̀͠į̷̳̳̯̪͔̩̕͢ͅͅͅǹ̛̰̠̱͇̗͇̣̥̙̥̭̜g͏̶̱̠͕̗͈̳͙͞͞ ̴̶̧̗͕͕̭̮́͜c҉̷͙̱̤̻̲͇̫̪̥͔͖͖͍̗̭̯̘o̡̝̰̠̫͙n̴̴̢͖͖̘͎̞͕̦̬c̷̣̻̞̱̜̯̗͝͞e̫̫̝͇̖̪̭̪̫̯̠͓̮̘̗̠͘͞p̨̻̫̜̞̻̹̟̫̲̮̺̮̦̺̤̺̝̀͜t̵̪͙̲̯̩̻̮̯̯̺͎͈̺̝̦̬͕́̕.̧͓̖̻̳̮̙̬̤͟
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