Practiced. Blessed.

XP: 2.
Test Icons:

Commit only to a skill test you are performing, and only if the difficulty of that test is higher than your base skill value.

After you commit Signum Crucis to a skill test, add X tokens to the chaos bag. X is the difference between the test's difficulty and your base skill value.

David Hovey
Horror in High Gear #197.
Signum Crucis

This card is excellent in a Preston Fairmont deck, taking advantage of his base value of 1 in each skill. Since he's likely to be mitigating those with cards like Dark Horse and Lola Santiago, Preston can use this on a skill test that he's likely to pass and still put several tokens in the bag.

trgreiss · 81
Note also that base skill value is always 0 for Calvin. — StyxTBeuford · 12699
When Silas draws a willpower treachery he can commit this for a couple of blessings and then pull it back to his hand and do it again later. An Amanda with a lot of static intellect boots can tuck this under her ID to earn several blessing while investigating a tough location. — OrionJA · 1

Double Quick Learner + double Drawing Thin + Signum Crucis on a base shroud 4 for example adds 10-[base intellect] bless tokens(you might miss the fact that it's still comparing to your base value, your passive buffs or commited icons do not change this). Pretty sick.

And why would I wanna do this you ask? Because Ancient Covenant is extremely strong, and the more people in your team that can take it the more attractive this gets.

Erdjo · 301
And a mere 20XP +2x per Covenant! — MrGoldbee · 1233

Repeatable with Silas on high shroud locations for a steady stream of lots of bless tokens. Since it takes effect after being committed rather than after resolution, Silas can reap the benefit turn after turn. Maybe you'll even start succeeding on some of those investigates!

Graham · 109
High shrouds have a great test, but your team probably wants you doing something besides just adding tokens to the bag. And that might mean moving somewhere else. — MrGoldbee · 1233