Let's say I have a 10/10 trample n my opponent had no blockers but 2 Planeswalkers of different subtype would my overflow on trample allow me to kill the first and the 2nd Planeswalkers or just one and rest to player
Sorry just 1 plainswalker :) Think of them as players that you attack. You wouldn't kill one player and then trample onto the next player in a multiplayer game now would you? Teehehee
edit: oh and here is a plainswalker guide by WotC. Enjoy!
http://www.wizards.com/Magic/TCG/Article.aspx?x=magic/rules/planeswalkers