"It would make life a lot easier if it's f.e war day and we could even unban some minigames like Gladiator or Sharkday and make it a rule that crits have to be off for it."
Off-topic a little bit but... Why do you think these games are banned in the first place? It's not because it's unfair to the REDs or that the guards have crits, it's because it is literally a minigame that allows the BLUs to freekill anyone on RED.
Absolutely ridiculous to include this.
I also don't understand how it would make Warday easier? The BLUs (with crits) die most of the time to the RED's firepower if they work together properly.
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On topic
Wardens that are heavily experienced may want to turn crits off to challenge themselves, however most (if not all) guards are inexperienced or not good enough as a BLU to actually manage a team of REDs without crits.
I've tried it without crits with a team of 8 guards, it's nearly impossible to maintain control. I highly doubt any BLUs would actually want to turn crits off, as it gives them a lot of control and makes the rounds smoother overall. It's already easy to rebel as a RED even with the BLU crits. One shot that barely misses is all that's needed to get slapped to the ground and it ends up a freeday.