This card is extremely niche- but if you have the right space for it, it can become a powerhouse. I'm currently running an Extra Actions Dexter Drake and this might be the best extra action card in the deck - for 1 card and 1 resource, you get two free evades and extra actions, which you can stack into the same turn. This card doesn't solve any problems, and it's not going to be an early upgrade for anyone - but if you can get enough draws, resources, or play actions that the up-front cost becomes less important, it can be part of some silly recursion builds.
Uses (4 charges).
If Blur has charges remaining: Evade. For this evasion attempt, you may use instead of and get +2 skill value. If you succeed, spend 1 or 2 charges and you may take that many additional actions this turn. If you succeed by 0, take 2 damage.
Blur (4) for Mystics :
Let's compare to its main competitor: Mists of R'lyeh.
doesn't spend a charge spends charges to Evade only on success and provides extra actions. Blur has the capacity to kill most investigators if you decide to spend charges 1 by 1. often have pretty low Health and therefore it can be a dangerous game. The best way to mitigate it is either to know exactly your token pool: if there are -3 and -5 tokens in the chaos bag and you test at +4 or +6, you make sure that there is no risk for you. Mind the symbols tokens though.
• Mists of R'lyeh is the same price, has 1 more Charge (which compensates more or less the fact that Blur spends only on success) and gives you one extra skill value (+3 ). The extra action is less flexible: you may want to Evade and then Investigate rather than move immediately. The negative potential can be much more likely to happen but is often less problematic as you often run 2 copies of each of your cards.
Conclusion: Blur (4) is for with high that are sure to oversucceed every time, and Mists of R'lyeh (4) gives you higher chances of success, but the downside happens more often though I'd rather throw away crucial cards than die.
Blur (4) for Rogues :
Except Sefina Rousseau, most rogues have a low and use their to evade. So why would they use this card to use their to evade when they can do it normally?
Blur costs 4 actions: 1 Play action, 1 Draw Action and 2 Resource actions and brings you back 4 actions via its 4 charges. It is therefore break even. That enters the category of deck fillers, this one being rather expensive though.
The positive side is: it provides you 2 to 4 Unexpected Courage for Evasion tests. It also gives you a bit of flexibility by choosing the number of extra actions you need for example in case of a location that you do not want to finish your turn in, but throwing 2 charges in one go is a waste of the boost of skill value.
The negative side is: you may take 2 damages per use. 4 charges means that this card has the potential to kill any investigator that can take it if they have no soak.
Interestingly enough, Knight of Swords can protect you from the negative part of both Blur (1) Blur (4), but for that price and that amount of XP, I'd rather play Hot Streak, The Moon • XVIII and Trench Coat to have the same bonus, with soak instead of damage risk.
TL;DR: I think that Blur (4) is a very niche card that will most likely not be used in decks because 4 XP for break even is really too much. For , if you really lack Drawing, it can be an alternative to Mists of R'lyeh, but based on most Mystic's low health, I don't think it's going to see a lot of uses either.