So you mentioned some time a while back about investing in certain cards, and I’m kinda new to the game, so uhh... which type of cards should I be focusing on leveling for my teams?
*opens lecture hall* Well you SEE-
So I'm assuming you mean in this post when I said "if you’re relying on an ability, the permanent SSRs might be worth looking at over limited time cards"?
Every card has a Level (which caps at 100 for URs), and a Skill Level (which caps at 10 for every single card). Level is the one that is gained through using the card or paying grimm on it, and affects the point strength of the card. Skill Level is the one that is gained through obtaining duplicate copies of a card and affects the strength of the skill, and as far as I can tell it also effects how likely you skill is to activate.
It's difficult to get limited edition cards to a level where they'll activate reliably enough. Sometimes you pull lots of one card trying to get another (like my Level 7 Asmo's Acrobatics), but a card is likely not going to be above level 5 if it isn't permanently available. So if you're going for sheer power level, the limited gacha and event cards are absolutely viable and not any stronger/weaker than the permanent ones. BUT if you're hoping for a skill to activate, then you should really be looking at the permanent SSRs in particular.
Before I list the ones I think are most useful, I'll point out two pieces of good news!
Support cards are relatively likely to activate as long as their listed prerequisite is met in battle. More likely than character cards, at least.
Cards that reflect an effect back at the enemy are also more likely to have that reflect skill activate than their other skill.
So here's the cards I recommend investing in as you're basically guaranteed to be able to get these cards to skill level 10 eventually:
Resentment Runs Deep (Envy Levi): Resentment Runs Deep my beloved. This card has Refresh Team, which is in my humble opinion the very best ability in the whole game. If it activates, it makes your ENTIRE team unaffected by the enemy's skills for as long as it's active. Seriously, if you can't beat a level, I recommend replacing the weakest card on the team (or the Levi card) with RRD and giving a rainbow glow stick to the strongest card. RRD activating is easier to rely on than the enemy skill NOT activating, and the glow stick will make up for the lost power level. ALSO, one of RRD's boosted sins is Sloth. Really, it's the best card in the game.
Living the Dream (Greed Levi): This card has Protect Gauge, which will make the enemy's next successful attack not harm your total score as much. Very useful for those battles where the enemies keep using their skills when you can't counter them and setting your points back JUST too low
One Too Many Insults (Pride Mammon): Are you plagued by that one UR card on your team that was really good but is slower now? This card has the chance to speed up the skill gauge for that card so you can try for that full 6 card multiplier combo a second time.
Any sloth SSR (Lucifer's Private Life, Hatred, Dust-Fighting Demon, Angel's First Horror Game): Not for any particular skill that they have, but because the paralysis skill is only found in battles with Sloth as one of its sins, and you want your team in those battles to have a high enough total strength to have a chance even if one of them gets paralyzed.
In general, cards that boost YOU (ex: The Mammon Way, Lucifer's Private Life) are more useful than ones that hinder the enemy (ex: Being the Oldest, Guided by Desire). If there's an actual threat of the enemy beating you to the top of the gauge, your cards aren't ready for that battle yet regardless of the skills.
Also, two cards are VERY situational. Beel's Morning (Lust) prevents opponents from using their skills at all, and Proud Brothers (Lust Asmo) prevents them from countering you specifically. Sometimes that's useful! Sometimes it's detrimental. It'll depend on the battle. Unspoken Affection (Gluttony Beel) is also situational, but probably a little more useful than the other two.
Anyway, I hope this gives you a starting point! All card have their uses, but the three specific ones I listed have the most useful skills
