Sentry ability commands in Zombie survival

[morsecode01 (Joey Morse)]

This should be a fairly simple question to answer but i was just wondering how do you upgrade sentries and get different types?

[Quinci]

Information page for abilities

Zombies Abilities

This post is a wiki, anyone can edit it. Please correct any mistakes or missing content. Information Abilities will have either or both of a passive and active part. A Passive part of an ability is something that happens automatically without manual input, whilst an active part of an ability is one that requires manual input to trigger. Almost all abilities give a 25% price increase for buying items in maps (ammo, weapons, armor, etc…), and the sentry ability has a price increase of 75% instea…