Pixel Strike 3D

I dont know how many XP but Im currently sitting at level 36 and I need to win 3-5 matches to get up one level at prestige 0.

about 40k XP for the last few levels, i average 15k per full CTF game (about 90 kills per game on average, many above 100 with peaks at 20k XP max.).
i have 21h40 on record and JUTS got my 1st Prestige, playing almost exclusively CTF games, 70% winrate, 4+ KD, 90 kills average per game, with lots of games against Mobile/PC cheaters. game is stupid

to add to everything:
If you want to make the grind a lot more efficient, the Elite status doubles your XP Gains for the entire status duration, 24h, 72h, or 1 week depending on what you bought.
I would recommend getting 750 Credits and buying one Battle Pass with that then switching Pass everytime you reach lvl 30 to keep the small Boost from being a BP owner and to get more Gold and Credits for the other achievement's progress.
More Credits also means you get to buy Elite status more often.
You also can buy the VIP status for $1.99 which afaik stays forever and lets you get a 20% Gold Boost and a 2x Challenge Rewards Boost which also will give you more Credits and Gold from Daily Challenges.
Overall on a 100 Kills CTF Game you're looking at 1 game for the first 10 levels and 2 to 3 Games per level from level 50 to 60.
Try to keep 3000 Gold for Prestige so you can buy your stuff instantly, otherwise play a few games to grind the early levels which will reduce the cost of late weapons drastically, by thousands.
I reckon this could take about 100h to 150h for an average player.
I'm entering Prestige 4 rn and have 40h on record, knowing i didn't have any Elite status for the first 2 Prestiges. But i also average 90 Kills per game, FAMAS or AWP makes this ridiculously easy. Also Quick Match lobbies are Xbox Only but the XP ranges from 3000 to 5000 for a 5min game which never happens because Xbox players barely shoot back. Compared to a 20000 to 40000 XP per 15min game in a good CTF game I believe we know what to play.
Some people talk about Bomb Defuse being very good for XP Grind, I didn't see it that way.

there is barely any cheaters in any of these modes. i have about 30k kills in CTF alone, im in DRQE Clan, a CTF grinding clan, 7th highest Rank in all-time clans leaderboards, there are cheaters but they get banned in the day, and i oersonally never met anyone going blatant, just suspicions.

I second not ever seeing a cheater even once so far and I'm already prestige 3.5. Going further than this, though, suicide (in-game) is also a possible option if you're not the best at the game. After killing yourself more than once in a row you get payback medals for doing it. If you do it with a grenade which is a guaranteed death if you throw it under yourself it's also a headshot medal. So you can get the exp of a full kill by repeatedly suiciding with a grenade. Not the fastest method but something I found out by accident when I got bored.