Magik was my first 5*, first ever r4. I took her to r4 after I did 5.4 initial completion. I awakened her with the mystic ag I got from exploring 5.4. She put in a lot of work against the collector when I went for act 5 100%. The collector is pretty aggressive so you can intercept him a lot and bait heavy by holding block, it's just about getting to your first sp2. Once you're there, you'll have a very good time. Transferring bane is easy and you can do slow combos to ensure you're having very good bane transfers. Since he's aggressive backdraft intercepting is very easy, if you're not comfortable doing stand-up intercepts, you could just block and bait heavy after you knock him down each time with your sp2, if you can nail those stand up intercepts then go for it! You'll have a fun time.Only thing to look out for is your power locks/power steals failing eventually coz of his fun and interactive ability which reduces your ability accuracy over time (2.5% every 5 seconds I believe, I could be wrong though)My personal best against collector with my r4 was a 57 hit combo. I r5ed her after exploring act 5, she was my first r5... No regrets about it. Also, running suicides greatly benefit her, she just rewinds the health she loses from recoil. The mastery build I used for act 5 with magik were full suicides (although it's better to run only DE, coz she nets a heal every time she activates her sps if you have recovery maxed) and with 3/5 MD.Enjoy the rank up and practice intercepting, mainly the backdraft ones and stand ups if you are comfortable.She's a great choice for r4.Have fun mate!