Forum:Best class ability purchase

Hi. I need some advice on which ability to purchase with my guild coins. I have leveled up all my characters to level 5, but I usually use rogue for festival guild wars with Deianira as my general. In guild battles, I am usually cleric, using either Sanna or Deianira. I have purchased heal 1; I have also cleanse 1, as well as evade ! Now I can't decide which to buy. I am torn between poison, or ambush for my rogue character. Am also considering fortitude or dispel for my cleric character. Although I have never used mage, I am impressed by the confuse and polymorph abilities. LOL... so much choices. Thank you.