Is the treasure
a Chest from the video game Bayonetta, found by finding an Umbra Witch's final resting place?
For me to receive this treasure, I had to wait for quite some time,
It takes a lot of time to find each Chest.
A time I did pass with leisure, many obstacles I had to climb.
Playing the video game is considered leisure, although there are many obstacles.
Never ceasing, I continued day by day.
You could play it every day.
Always piecing, many foes I did slay.
Bayonetta is a "hack-and-slash" game.
To receive a prize, one most precious indeed.
The Chests are extremely precious in the game.
I widened my eyes, until I did succeed.
Maybe this is a reference to the state of one's vision after playing for so long?
Can you tell me what I've gotten? It's the first of it's kind I've received.
It could be the first chest, or the first Silver award you've received?
The secret hint
FANATIC could be used to describe the achievement TREASURE FANATIC, which is earned once all of the Chests/final resting places have been found.