Here is the full list of all 11 Telmari Demo achievements.
Bounce on four plunger arrows.
Bounce on a three plunger arrows.
You beat the Ancient One ten times.
You have died a total of fifty times.
Meet the dodo for the first time.
You have died ten times.
Died to spines for the first time.
You have convinced the ill tempered Ancient One to accompany you.
You beat the Ancient One for the first time.
First death.
You have completed the tutorial.