1 - One is Reflection: it instantly is fired back at them
2 - Another is just blast with the Variable Special Effect advantage with a limitation that they can only use it after they have been exposed to that special effect (within x time period) (probably a -¼ at most)
3 - You can do a variant with that gives them absorption that gives them END which they can only use to fire off the #2 option, so that they literally are only able to use it with an absorb. This would negate the limitation (since they already cannot use it without the absorb) and I'd build with an END Reserve that has no recovery, just a potential power source for the blast.
4 - You could build a multipower with various blasts in it with the "only after having been exposed to a special effect" limitation on it, with each slot a different kind of attack. This gives you options that the #2 does not such as a KA, a drain, etc. This could work the same way as #3, drawing only from the non-recovering END Reserve.
I recently upgraded to MacOS Catalina, and had the same problem. The issue is that Catalina has very strict file permissions. I was forced to go to System Preferences -> Security & Privacy -> Full Disk Access
From there I added /System/Library/CoreServices/Jar Launcher.app
My Mac is now less secure, but at least Hero Designer can find my characters!
