Are weekly challenges per character or per account?

[Mark]

Weekly ritual challenges for like vanguard where you get pinnacle gear and exotics are they just for one account per week or if you have 2 characters above 1750 they both get weekly challenges? Does this also apply for weekly bounties as well?

[Ixamesh]

Per class

[Ixamesh]

You can't use 3 titans to level up faster. You can still level faster using different classes because weapons are shared. You can also use your highest level character to buy exotics from Xur and level other classes over time without playing them.