Answer

Based on the rulebook context:

• The Veil attribute is defined as: "This Unit cannot be targeted by enemy Rituals or Abilities."
  (See page 21)

• There is no further elaboration in the provided context about the difference between targeted and non-targeted (global) effects.

• The example for Veil specifically uses the word "targeted," implying that only effects that specifically choose the Veiled Unit as their target are prevented.

• A global Ritual that affects "all Units" does not target any specific Unit; it applies its effect to all Units simultaneously.

Conclusion

A Unit with Veil is only protected from Rituals or Abilities that specifically target it. If a global Ritual affects all Units (such as "all Units take damage"), the Veiled Unit would not be protected and would be affected by the Ritual, because the effect is not targeting it specifically.

This answer is based on the definition of Veil on page 21, which states it prevents only being "targeted" by enemy Rituals or Abilities, and does not mention immunity to non-targeted or global effects.

Source: page 21.

Source: Core Rulebook (pp. 15, 20, 21, 24, 25)