athene's working on heal is something kind of niche i feel? it's alright, but i feel like if it were actually used a lot it would bring about the two-tier nerf sandwich in hitting both heal and then athenes and leaving both feeling shitty (or even shittier)
i wonder if it's intended, but it might lead to an increase of flash/heal karma or lulu
catalyst passive feels really underwhelming unless you're a mage with large mana costs- yeah the healing adds up over time, but it takes so long for it to feel meaningful on champions like the aforementioned orianna given that your Q is going to heal you for less than 5 health until level 9. the upgrade into rod like i talked about earlier just feels underwhelming. however, i feel like tear into catalyst would be a really good combo IF the heal accounted for the mana cost before the 15% given back to you- maybe something to try sometime? as an item it just doesn't feel nearly as powerful as it did in the beginning of the season when it was a giant stat stick. i miss the old passive of health/mana restore on level up, because it cushioned laning into bad matchups
i don't feel like you should be building morello's if youre looking for defensive stats, in that case a hourglass or abyssal rush would make a lot more sense (especially now that they both give CDR in their path !!!!) as well as both being really efficient now. morello's feels like an item meant for pokey, zoning mages who are going to get assists in a fight no matter what unless their team gets flat out obliterated (in which case, unlucky, and itemization can't really save you if you get clean aced)
i disagree with not taking morellos into other passive matchups if you aren't ahead though- relatively cheap CDR and mana in codex/lost chapter can help with lane phase. the only matchup that would make me hesitant is into zed, but that's natural because you either take hourglass, eat shit, or make HIM eat shit if he's bad. likewise, the only time i would think about athenes if if i WAS incredibly behind and was basically relegated to shield/wave bot. it feels almost like building ardent censer albeit with a different interaction on sheilding- decent and viable, but only something you would do if you're a secondary carry with a MASSIVE primary threat, or a tertiary carry who got fucked in lane but still stays relevant because of your natural ability to fall back on utility that, regardless of the damage you do or not, can swing fights with a well placed shockwave
i put entirely too much thought into it but tldr
-heal/athene's is a weird interaction that i overlooked but wouldnt put too much stock in given that most mids dont take heal (azir, some orianna players, xerath are the only three that come to mind immediately)
-catalyst/roa feel underwhelming unless you set up your entire build to take advantage of it by going roa/seraph's and getting something like +198 mana from seraph passive. seraph's actually feels really nice with all of the flat mana in builds now!
-defensive mage items feel better to build. abyssal has a cheaper combine cost if you get all three parts and zhonya's doesnt feel like a "sit on one component for 12 minutes trying to get gold for the completion" anymore, with it's cheaper AP component- even though it gives less damage, it feels better than it did.
-morello>roa>athene's if ahead, roa/seraph's>morello>athene's if itemizing to build around it, and athene's>morello>roa if you're that 1/4 mid that's just getting camped to shit but you have a threat in bot and either top/jungle that can carry in your place
side note, cass rework feels incredibly hit or miss. you either stomp or get stomped, without any middle ground.