I followed the advice of many solutions available here on TrueAchievements and on the web. On one thing they all agree, keep the combo for as long as possible and get as far as possible with the multiplier to get enough experience to level up quickly.
To achieve this we must first of all have an equipment that makes us gain focus and that it increases the duration of it. Subsequently choose Jupiter as god to its gain of focus resulting from executions and familiarizing with the map, where the enemies are generated and where they came from, so you can use wisely the focus and the taunt.
The taunt is used as much as possible between the waves of enemies to freeze your combo chain while the focus will allow you to fight and do executions without worrying about being hit. The duration of the taunt is about 15 seconds, so if you see that your multiplier flashes use the taunt.
In my opinion the best map is without doubt Revolution. After the initial phase, you will be given the task of using the Scorpio to protect the bridge, climb up and activate the Scorpio with
but exits immediately after it has been activated by pressing
again without shooting any enemy, go down from the platform of the Scorpio and wait for the enemies approaching from the bridge. Here starts your combo chain that if you are careful enough, you can bring to the end of the round.
With a little practice and knowledge of the map, you can get without too much trouble a combo of 450, or even 600 if you do not make mistakes, it requires a little practice but pays off, we speak of over 500,000 EXP in the event of a combo over 600!
Below I posted a video from one of my games where I got a combo of 597 but in my best game I got a combo of 621 with over 560,000 EXP as a reward.
I hope you find it useful and for any questions or concerns please comment below.
Have fun in the arena.
Edit: I restored the video that for some reason had been removed.
Edit 2: Added another video with better gear, combo and xp.