2017-03-23 00:03:42.410 summaryGame[6669:273050] *** Terminating app due to uncaught exception

'NSUnknownKeyException', reason: '[<summaryGame.ViewController 0x7fd5025096c0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key replyButton.'
*** First throw call stack:
(
0 CoreFoundation 0x0000000110024d4b __exceptionPreprocess + 171
1 libobjc.A.dylib 0x000000010d33721e objc_exception_throw + 48
2 CoreFoundation 0x0000000110024c99 -[NSException raise] + 9
3 Foundation 0x000000010ce459df -[NSObject(NSKeyValueCoding) setValue:forKey:] + 291
4 UIKit 0x000000010d9a1293 -[UIViewController setValue:forKey:] + 88
5 UIKit 0x000000010dc1579e -[UIRuntimeOutletConnection connect] + 109
6 CoreFoundation 0x000000010ffc99e0 -[NSArray makeObjectsPerformSelector:] + 256
7 UIKit 0x000000010dc14122 -[UINib instantiateWithOwner:options:] + 1867
8 UIKit 0x000000010d9a79c5 -[UIViewController _loadViewFromNibNamed:bundle:] + 386
9 UIKit 0x000000010d9a82e7 -[UIViewController loadView] + 177
10 UIKit 0x000000010d9a861c -[UIViewController loadViewIfRequired] + 201
11 UIKit 0x000000010d9a8e70 -[UIViewController view] + 27
12 UIKit 0x000000010d8724b5 -[UIWindow addRootViewControllerViewIfPossible] + 71
13 UIKit 0x000000010d872c06 -[UIWindow _setHidden:forced:] + 293
14 UIKit 0x000000010d886519 -[UIWindow makeKeyAndVisible] + 42
15 UIKit 0x000000010d7fef8d -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4818
16 UIKit 0x000000010d8050ed -[UIApplication _runWithMainScene:transitionContext:completion:] + 1731
17 UIKit 0x000000010d80226d -[UIApplication workspaceDidEndTransaction:] + 188
18 FrontBoardServices 0x000000011176e6cb __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 24
19 FrontBoardServices 0x000000011176e544 -[FBSSerialQueue _performNext] + 189
20 FrontBoardServices 0x000000011176e8cd -[FBSSerialQueue _performNextFromRunLoopSource] + 45
21 CoreFoundation 0x000000010ffc9761 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
22 CoreFoundation 0x000000010ffae98c __CFRunLoopDoSources0 + 556
23 CoreFoundation 0x000000010ffade76 __CFRunLoopRun + 918
24 CoreFoundation 0x000000010ffad884 CFRunLoopRunSpecific + 420
25 UIKit 0x000000010d800aea -[UIApplication _run] + 434
26 UIKit 0x000000010d806c68 UIApplicationMain + 159
27 summaryGame 0x000000010cd5572f main + 111
28 libdyld.dylib 0x0000000110fd468d start + 1
29 ??? 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)

Проверяй аутлеты

В трех словах, сториборд думает что у тебя в классе есть пропертя с названием replyButton, потому что ты ее раньше туда сделал.