could it be better that pierce has a static number? like pierce 2 would do 2 damage to the attackers target when blocked (and if you still wanted the thorn elemental feel you could reduce its power by the pierce number). would remove the need for having to work out rounding up/down on even powers and you could print all the cards with pierce to functionally do the same damage as it would in the original post.
i would also make that planeswalker cost 4 mana or have it start with 1 less loyalty as its ultimate is pretty good for something that can go off on turn 4 fairly consistantly (mana dork or proliferate spell)
i would also make that planeswalker cost 4 mana or have it start with 1 less loyalty as its ultimate is pretty good for something that can go off on turn 4 fairly consistantly (mana dork or proliferate spell)