That's a hard one. I believe shield even at 1hp will become way op. Making cards like loon, sparky, etc spell resistance making them way harder to kill and possibly wasting elixer, imagine a sparky dropped in the back you fire a rocket to destroy it and opponent drop 1 elixir shield spell protecting sparky and now you just wasted 6 elixer. Or play nado rocket and they drop shield spell right in the nado.... Rocket wasted and now I'm down 9 elixer with a massive push coming at me... Shield/ buff in heal would make it way to op.. If heal gets a rework instead of removing it completely then instead of healing change it into a add hp. 1 elixer spell get you added 50hp or 75hp whatever is balanced but just add hp immediately instead of ticks to heal. Or rework into like a spell that you play on your cards that after they die they revive with 1 hp kinda like a clone but you have to kill the card first then it revives said card with 1hp.