Liar's Isle is a set of knights and knaves logic puzzles. Every islander is either truthful, meaning everything they say is true, or a liar, meaning everything they say is false. Each one makes a single statement, perhaps about another islander, about who is the same kind, or about how many tell the truth. Read the statements, then mark each islander Truthful or Liar.
A mark is accepted only when it is proven. If what you have heard still allows both answers, the game refuses the mark with a gentle "Not proven yet" and no penalty. A mark that clashes with the statements is refused too, and counts as a mistake. On later islands only a few people speak at the start; the others stay silent until you prove what they are, and then their words join the puzzle.
Sixty islands run across five tiers, from Beachcomber to Oracle, growing from three or four islanders to as many as eight, and there is a daily island. You start with three stars, and each mistake or hint costs one, down to a minimum of one. The hint marks the next provable islander and explains why.
Worked example
Ana says, "Bo is a liar." Bo says, "Ana and I are the same kind." Suppose Bo tells the truth. Then Ana is truthful as well, so her words are true and Bo is a liar, which contradicts the supposition. So Bo is a liar. His statement is therefore false, which means Ana and Bo are different kinds, and Ana is truthful.
Strategy tips
Try a "what if". Assume one islander is truthful and follow the chain. A contradiction proves the opposite.
Flip a liar's words. Once someone is proven a liar, the opposite of their statement is a fact you can use.
Watch the counts. A claim about exactly how many liars live on the island ties every islander together.