Oh, what’s the point.
nm.
I’m not following you here buddy. what are you talking about?
Well, I was going to say something about how good he was, but I changed my mind.
ah, okay. He might get better the higher his level gets. That’s what other people tell me, before reaching level 30 he’s basically a glorified rune trash can
He’s ok at low levels, but yeah he doesn’t really kick into high gear until his 1st ability hits level 3. And once he hits 50 he’s unstoppable.
I really wish PVP existed so I could test this theory of yours 
Though I did finally see a bit of his potential. AI with Karn cascaded ~20 times and was able to play his entire hand, got a 50/50 something Karn token out. Was impressive, but then I stole it and defeated him with it, but I’ll admit that glimpse made me consider that he may not be as bad as the AI runs him lol
I’m still struggling to level him, but I have found that in legacy events, you can do some good stuff with him using the eldrazi cards from BFZ and EMN since they are decent sized creatures and are colorless when you exile them for the mana boost from his first ability.
Can’t speak to playing him when he gets a bonus from exiling colored cards.
Wereotter, FindingHeart8, I think you guys are both missing the point entirely; also, forgive me if this comes across as rampant pedantic nonsense.
You need to play him with a color palette that’s as full as possible instead of just focusing on colorless creatures. If you only focus on colorless cards, you’re going to max out the utility of his first ability after three uses.
On the other hand, varying the colors of the cards in your deck means that every time you use his first, you’ll likely improve your mana gains. Furthermore, it gives you the added benefit of being able to freely dig through your deck for the cards you actually need.
I could also go on and on about using him with StV, but I don’t think there’s much that needs to be said there.
Back to OP’s point, I think what he’s getting at is that Karn is really quite ridiculous. His ability suite is absurdly cheap at all three levels, and, two of them are incredibly useful. The first is like Strategic Planning on steroids, the third is an amalgam of Hannah and Nyx, and the second (arguably the least useful of the three, though that label is still somewhat of an injustice) is essentially Talent of the Telepath. Really, his only downside is that he’s limited to the colors of whatever node you decide to assign to him.
My point was more that if you haven’t leveled him up enough, like me, then you don’t get any bonus off his first ability unless you’re exiling a colorless cards, hence why I mentioned that I’ve been using Zendikar and Eldritch Moon cards to at least have him playable while going through the process. You don’t start getting a mana bonus on colored cards off that first ability until it’s at level 3, at which point I could change my suggestion to using as many multi color cards as possible to more quickly max out mana gains.
As far as leveling is concerned, I guess that’s a fair enough argument. I admit that I took for granted the fact that I was able to push him straight to 60 when I got him. Push through to 35, as that’s when he starts taking advantage of colored cards with his first!
Low levels, using colourless stuff, I found Scrapheap Scrounger and Riddleform it’s usual wonderful self, then the cheapest things I could find, like Lethal Sting and stuff.
I was able to lvl him to 60 right after I got him. He is definatly a powerhouse. I seldom use his 2nd or 3rd ability unless I’m creaturless.
I can feel OP a bit here. I got him when he was available for 10 bucks. In the beginning I used him a lot just thowing in the best cards of every color I had. I won a lot of games because of his third ability, but Karn never felt like totally dominating. Now as I levelled him to 55, I barely use him, because of the lack of ideas.
Does anyone have some good ideas for Standard to make him great?
He is the best commander for a lands deck, I guess. His first ability synergizes with land supports, and he benefits from you playing different color converters.
Yup. But if no-one minds the game being unbalanced, there’s hardly any point writing a long screed about it.
The fact that he’s not so good at level 30 doesn’t change the fact that he’s… oh, look, I’m doing it. I’ll stop now.
I made a rainbow deck that is absurdly fun to play. Just throw in every multicolor card you can find (the more colors the better) and laugh as you get to +7 in every color almost instantly. As long as you have some reliable draw you’re basically dumping your hand every turn.
I’m still not sold that he’s this all powerful planeswalker. This is only a standard deck (pre-M19) so maybe he could do more with legacy: