attack:
deducts current attack points
from opponent's health
power up:
increases attack points randomly
(+2, +4, +6, +8, or +10)
each power up costs 5 stamina points
lose turn:
no increase in attack points
and loses turn to attack
stamina:
used to buy power up points
regenerates by 10 points after each attack
health:
indicates health status / survival rate