Most notably UD/FW, since I mostly play ST, FS and a little SP, I don't have access to decaying etc., so I'm not sure how I'm meant to stop things like Maguses just balling out of control and wiping all of my champs out by spamming blood magic
To deal with magnus specifically, you want to try and keep your champions apart from each other and focus him at range. For fs, try triggering perseverance and using something like slipworm to trigger his death. Magnus is crowd control, simply try to avoid being a crowd. Also for FS you may try drowning him. In SP you can distract him with alot of distracting champions., or like whispers of the mind. Otherwise, just try to wear them down, focus the units one at a time to make sure they can't heal.
The key to beating any deck that has healing capabilities is not to spread out damage - Make sure to try and focus fire one champion and kill it completely in one round. If you can learn to do this, you'll win a lot more than you lose.
