Summoner's MP issues

[Ryuko]

I once had a long argument with a Summoner about using Fester. He insisted Fester wasn't worth it and he would go OOM if he used it. He literally NEVER used Fester... It seems like the OP has the opposite problem. Summoner has a LOT of stuff in our arsenal. Yes, sometimes using Energy Drain is necessary... but if you HAVE to use it, make sure to do so BEFORE you are almost oom. That way, you can maintain nearly 100% DoT uptime even without the filler Ruin 1s and Festers. Needing to go into 'mana conserve mode' is not terrible for a Summoner... After all, our DoTs alone are a pretty decent chunk of our damage... and don't forget that our pet is ALWAYS hitting, too. However, going COMPLETELY oom will seriously mess up your rotation and cause your DoTs to fall off and not be refreshed. One of the most important things to remember is to use your Aetherflow on cooldown. Plan your Festers and Energy Drains ahead of time so you aren't wasting the cooldown of Aetherflow, either.

[neizero]

Always Be Casting, if you stop for any reason you are likely losing dps. Especially true for fester as it is hard capped to 3 per min

[horaiyo]

During a non-rs rotation, sure, but not during rs. Not casting the second fester before rs drops is definitely a dps loss compared to waiting half a second for bio to register before hitting fester.