played all the battles here's what I think about it:
pretty satisfying system of using cards, however there are some issues with it. You are somewhat incentivized to spam cards due to losing momentum if you take too long, that means that you are more incentivized to build a more simple deck using cards that are more stat oriented rather than synergy oriented. your given too many link cards at the start with not much information on them while not having a lot of start cards. A lot of the zero energy cards with start are good simply because it increases momentum and allows you to play link cards. I think there should be a menu for each different effect or a tutorial on how linking works, also it would be nice to be able to skip the tutorial if you want.
boomerang seems quite strong due to you being able to potentially going for a power build and probably getting boomerang since there's not a lot of backpack items currently. Maybe give boomerang 3 uses and then it breaks?
Best cards (I think)
warrior: flex and battle cry, both cards give power and start which is very good.
rogue: backflip and boot knife, boot knife gets you a kunai which lets you start or link as long as you don't get hit, backflip lets you start or link while also letting you dodge.
neutral: throwing dagger, parrying dagger, both cards deal 3 damage for 0 energy which is very nice with momentum since you can cycle damage quicker, parrying dagger does require you to break but that's pretty easy once you get a few start cards.
haven't played the other class.
one potential way to solve the momentum problem would be having the ability to swap out momentum for a different ability that wasn't time oriented that triggers like playing 3 weapons gets you 1 power or something like that.
Overall it's a pretty fun deckbuilding game with a lot of potential, it does seem a bit tricky to balance though since your incentivized to play simple strategies and not do anything too complicated due to momentum.